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How the numbers work: running a business

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ROI Guide

The ROI Formula

  1. ROI = (Current Value - Original Investment) / Original Investment × 100
  2. Or:
  3. ROI = (Gain from Investment - Cost of Investment) / Cost of Investment × 100

Simple Example

  1. You invest $10,000 in shares
  2. After 2 years, your investment is worth $12,500
  3. ROI = ($12,500 - $10,000) / $10,000 × 100
  4. ROI = $2,500 / $10,000 × 100

ROI = 25%

Annualized ROI

  1. Investment: $10,000 → $12,500 over 2 years
  2. Total ROI: 25% (as calculated above)
  3. Annualized ROI = [(12,500/10,000)^(1/2)] - 1 × 100
  4. = [1.25^0.5] - 1 × 100
  5. = 1.118 - 1 × 100

= 11.8% per year

Common Applications

  1. Buy shares: $5,000
  2. Sell shares: $6,200
  3. ROI = 24%

Common Applications

  1. Purchase price + costs: $500,000
  2. Sell after 5 years: $650,000
  3. ROI = 30%

Common Applications

  1. Machine cost: $100,000
  2. Profit generated over 3 years: $140,000
  3. ROI = 40%

Common Applications

  1. Campaign cost: $20,000
  2. Additional revenue generated: $75,000
  3. Profit: $55,000
  4. ROI = 275%

Example 1: Share Investment

  1. Initial purchase: 1,000 shares at $15 = $15,000
  2. Brokerage fee: $30
  3. Total investment: $15,030
  4. After 18 months:
  5. Share price: $19.50
  6. Dividends received: $750
  7. Sale value: 1,000 × $19.50 = $19,500
  8. Sale brokerage: $30
  9. Net proceeds: $19,500 - $30 + $750 = $20,220

Example 1: Share Investment

  1. Total gain = $20,220 - $15,030 = $5,190
  2. ROI = $5,190 / $15,030 × 100

ROI = 34.5%

Example 1: Share Investment

  1. Time period: 18 months = 1.5 years
  2. Annualized = [(20,220/15,030)^(1/1.5)] - 1 × 100
  3. = [1.345^0.667] - 1 × 100

= 21.0% per year

Example 2: Rental Property Investment

  1. Property price: $650,000
  2. Legal fees: $3,000
  3. Building inspection: $500
  4. Initial repairs: $15,000
  5. Total investment: $668,500

Example 2: Rental Property Investment

  1. Rental income: $520/week × 52 × 5 = $135,200
  2. Expenses (rates, insurance, maintenance): $45,000
  3. Net rental income: $90,200
  4. Property value: $780,000
  5. Selling costs (agent, legal): $25,000
  6. Net sale proceeds: $755,000

Example 2: Rental Property Investment

  1. Total return = $755,000 + $90,200 - $668,500
  2. = $176,700
  3. ROI = $176,700 / $668,500 × 100
  4. Annualized: 4.8% per year

ROI = 26.4% (over 5 years)

Example 3: Business Equipment

  1. Machine cost: $12,000
  2. Installation: $800
  3. Training: $500
  4. Total: $13,300

Example 3: Business Equipment

  1. Additional coffee sales: $45,000/year
  2. Coffee costs: $18,000/year
  3. Maintenance: $1,200/year
  4. Net profit per year: $25,800
  5. 3-year profit: $77,400

Example 3: Business Equipment

  1. ROI = $77,400 / $13,300 × 100
  2. Annualized: 88.5% per year

ROI = 582%

Example 4: Marketing Campaign

  1. Ad spend: $5,000
  2. Creative design: $800
  3. Total cost: $5,800

Example 4: Marketing Campaign

  1. Revenue from campaign: $28,500
  2. Cost of goods sold: $11,400 (40% margin)
  3. Gross profit: $17,100
  4. Campaign cost: $5,800
  5. Net profit: $11,300

Negative ROI (Losses)

  1. Investment: $20,000
  2. Current value: $14,000
  3. Loss: $6,000
  4. ROI = -$6,000 / $20,000 × 100

ROI = -30%

🌍 Real-World ROI Examples

  1. Investment: $100,000 for 10% equity
  2. Company valuation: $1,000,000
  3. Time: 5 years

🌍 Real-World ROI Examples

  1. Company sold for: $8,000,000
  2. Your 10% share: $800,000
  3. ROI = ($800,000 - $100,000) / $100,000 × 100
  4. Annualized: 51.6% per year

ROI = 700%

🌍 Real-World ROI Examples

  1. Company IPO valuation: $3,500,000
  2. Your 10% stake worth: $350,000
  3. ROI = 250%
  4. Annualized: 28.5% per year

🌍 Real-World ROI Examples

  1. Company bankrupt, assets sold
  2. Recovery: $5,000 (creditors paid first)
  3. ROI = -95%

🌍 Real-World ROI Examples

  1. Solar panels + installation: $15,000
  2. Government rebate: -$2,000
  3. Net investment: $13,000

🌍 Real-World ROI Examples

  1. Electricity bill reduction: $1,850/year
  2. Feed-in tariff (sell excess): $280/year
  3. Total annual benefit: $2,130
  4. Maintenance cost: $100/year
  5. Net annual savings: $2,030

🌍 Real-World ROI Examples

  1. Total savings: $2,030 × 10 = $20,300
  2. ROI = ($20,300 - $13,000) / $13,000 × 100
  3. Annualized: 4.6% per year
  4. Payback period: $13,000 / $2,030 = 6.4 years

ROI = 56.2%

  1. Training course costs: $50,000
  2. Lost productivity (time away): $25,000
  3. Total investment: $75,000
  1. Productivity increase: $45,000
  2. Error reduction savings: $18,000
  3. Faster project completion: $22,000
  4. Total benefit: $85,000
  1. Year 1 benefit: $85,000
  2. Year 2 benefit: $75,000 (slight decline)
  3. Year 3 benefit: $65,000
  4. Total 3-year benefit: $225,000
  5. ROI = ($225,000 - $75,000) / $75,000 × 100
  6. Annualized: 44.2% per year

ROI = 200%

  1. Contribute $300/month + employer match $150
  2. Total contribution: $450/month × 12 × 35 = $189,000
  3. Average return: 7% per year (growth fund)
  4. Final value at 65: $738,500
  5. Gain: $549,500
  6. ROI = $549,500 / $189,000 × 100

ROI = 291%

  1. Save $450/month × 84 months = $37,800
  2. Use as 10% deposit on $380,000 property
  3. Property value after 28 years: $950,000
  4. Mortgage paid off, own outright
  5. ROI = ($950,000 - $37,800) / $37,800 × 100

ROI = 2,413%

WACC Explained

The WACC Formula

  1. WACC = (E/V × Re) + (D/V × Rd × (1 - Tc))
  2. Where:
  3. E = Market value of equity
  4. D = Market value of debt
  5. V = E + D (total market value)
  6. Re = Cost of equity
  7. Rd = Cost of debt
  8. Tc = Corporate tax rate

Simple Example

  1. Equity: $6 million (60% of capital)
  2. Debt: $4 million (40% of capital)
  3. Cost of equity (Re): 12%
  4. Cost of debt (Rd): 6%
  5. Tax rate: 28%
  6. WACC = (0.60 × 12%) + (0.40 × 6% × (1 - 0.28))
  7. WACC = 7.2% + 1.73%

WACC = 8.93%

Components of WACC

  1. Re = Rf + β × (Rm - Rf)
  2. Rf = Risk-free rate (government bonds)
  3. β = Beta (stock volatility vs market)
  4. Rm = Expected market return
  5. (Rm - Rf) = Market risk premium

Components of WACC

  1. NZ government bond rate: 4.5%
  2. Company beta: 1.2
  3. Market return: 10%
  4. Re = 4.5% + 1.2 × (10% - 4.5%)
  5. Re = 4.5% + 6.6%

Re = 11.1%

Components of WACC

  1. Total interest expense: $300,000
  2. Total debt: $5,000,000
  3. Rd = $300,000 / $5,000,000

Rd = 6.0%

Components of WACC

  1. Pre-tax cost of debt: 6.0%
  2. Tax rate: 28%
  3. After-tax cost = 6.0% × (1 - 0.28)

After-tax cost = 4.32%

Example 1: NZ Manufacturing Company

  1. Equity:
  2. Shares outstanding: 10 million
  3. Current share price: $8.50
  4. Market value of equity (E): 10M × $8.50 = $85 million
  5. Debt:
  6. Bank loans: $30 million
  7. Bonds outstanding: $20 million (at par)
  8. Market value of debt (D): $50 million
  9. Total value (V):
  10. V = $85M + $50M = $135 million

Example 1: NZ Manufacturing Company

  1. Weight of equity (E/V) = $85M / $135M = 63.0%
  2. Weight of debt (D/V) = $50M / $135M = 37.0%

Example 1: NZ Manufacturing Company

  1. Risk-free rate (NZ 10-year govt bonds): 4.2%
  2. Market return (NZX50 expected): 9.5%
  3. Company beta: 1.15
  4. Re = Rf + β × (Rm - Rf)
  5. Re = 4.2% + 1.15 × (9.5% - 4.2%)
  6. Re = 4.2% + 6.10%

Re = 10.3%

Example 1: NZ Manufacturing Company

  1. Total annual interest: $3.2 million
  2. Total debt: $50 million
  3. Rd = $3.2M / $50M

Rd = 6.4%

Example 1: NZ Manufacturing Company

  1. Corporate tax rate: 28%
  2. After-tax cost of debt = 6.4% × (1 - 0.28)

After-tax Rd = 4.61%

Example 1: NZ Manufacturing Company

  1. WACC = (E/V × Re) + (D/V × Rd × (1 - Tc))
  2. WACC = (0.630 × 10.3%) + (0.370 × 4.61%)
  3. WACC = 6.49% + 1.71%

WACC = 8.20%

Example 2: Comparing Capital Structures

  1. Note: Higher debt increases both cost of debt (6% → 7%) and cost of equity (11% → 12.5%) due to increased financial risk
  2. But tax shield benefit outweighs the risk increase
  3. WACC decreases from 9.00% to 8.77%

Lower WACC = Higher company value

Example 3: Project Evaluation Using WACC

  1. NPV = -$5.0M + $800K/1.082 + $1.2M/1.082² + ... + $1.5M/1.082⁵
  2. NPV = -$5.0M + $739K + $1,025K + $1,190K + $1,100K + $1,016K
  3. NPV = -$5.0M + $5.07M

NPV = $70,000 (Positive!)

Example 3: Project Evaluation Using WACC

  1. IRR = 8.5%
  2. IRR (8.5%) > WACC (8.2%)

Decision: ACCEPT PROJECT

Example 4: Valuing a Company Using WACC

  1. Sum of PVs = $11.0M + $11.8M + $12.4M + $12.7M + $13.0M + $162.5M
  2. Enterprise Value = $223.4M
  3. Less: Net Debt = $40M

Equity Value = $183.4M

🌍 Real-World WACC Examples

  1. Market cap (equity): $2,400M
  2. Debt outstanding: $1,600M
  3. Total value: $4,000M
  4. Equity weight: 60%
  5. Debt weight: 40%

🌍 Real-World WACC Examples

  1. Cost of Equity (CAPM):
  2. Risk-free rate: 4.0%
  3. Beta: 0.75 (utilities are stable, low beta)
  4. Market premium: 5.5%
  5. Re = 4.0% + 0.75 × 5.5% = 8.1%
  6. Cost of Debt:
  7. Average interest rate: 5.2%
  8. After-tax (28%): 5.2% × 0.72 = 3.74%

🌍 Real-World WACC Examples

  1. WACC = (0.60 × 8.1%) + (0.40 × 3.74%)
  2. WACC = 4.86% + 1.50%

WACC = 6.36%

🌍 Real-World WACC Examples

  1. Grid upgrade cost: $250M
  2. Expected return: 7.5%
  3. 7.5% > 6.36% WACC

Approve project (creates value)

🌍 Real-World WACC Examples

  1. Recent funding round valuation: $80M
  2. Equity: $80M (investors + founders)
  3. Debt: $5M (equipment financing)
  4. Equity weight: 94.1%
  5. Debt weight: 5.9%

🌍 Real-World WACC Examples

  1. Cost of Equity:
  2. Risk-free: 4.0%
  3. Beta: 1.8 (high volatility, high growth)
  4. Market premium: 6.0%
  5. Re = 4.0% + 1.8 × 6.0% = 14.8%
  6. Cost of Debt:
  7. Interest rate: 9.5% (risky borrower)
  8. After-tax: 9.5% × 0.72 = 6.84%
  1. WACC = (0.941 × 14.8%) + (0.059 × 6.84%)
  2. WACC = 13.93% + 0.40%

WACC = 14.33%

  1. Market cap: $350M
  2. Bank debt: $120M
  3. Bonds: $80M
  4. Total debt: $200M
  5. Equity weight: 63.6%
  6. Debt weight: 36.4%
  1. WACC = (0.636 × 11.74%) + (0.364 × 4.90%)
  2. WACC = 7.47% + 1.78%

WACC = 9.25%

  1. WACC reduction: 8.88% → 8.52% (36 basis points)
  2. On $200M enterprise value:
  3. Annual savings: $200M × 0.36% = $720,000
  4. Company value increase: ~$8-10M

Price Elasticity of Demand Guide

The PED Formula

  1. PED = (% Change in Quantity Demanded) / (% Change in Price)
  2. Using Midpoint Method (more accurate):
  3. PED = [(Q2 - Q1) / ((Q2 + Q1)/2)] / [(P2 - P1) / ((P2 + P1)/2)]
  4. Where:
  5. Q1 = Original quantity demanded
  6. Q2 = New quantity demanded
  7. P1 = Original price
  8. P2 = New price

Simple Example

  1. % Change in Quantity = (160 - 200) / ((160 + 200)/2) = -40 / 180 = -22.2%
  2. % Change in Price = (5 - 4) / ((5 + 4)/2) = 1 / 4.5 = 22.2%
  3. PED = -22.2% / 22.2% = -1.0

PED = 1.0 (using absolute value)

Why PED Matters for Business

  1. Current: $50 price × 1,000 units = $50,000 revenue
  2. Raise price 10% to $55
  3. Demand falls 20% (PED of 2.0) to 800 units
  4. New revenue: $55 × 800 = $44,000
  5. Result: Lost $6,000! Wrong move.

Why PED Matters for Business

  1. Current: $50 price × 1,000 units = $50,000 revenue
  2. Raise price 10% to $55
  3. Demand falls only 5% (PED of 0.5) to 950 units
  4. New revenue: $55 × 950 = $52,250
  5. Result: Gained $2,250! Good move.

Example 1: Coffee Shop Price Change

  1. Original price (P1): $4.50
  2. New price (P2): $5.00
  3. Original quantity (Q1): 300 cups/day
  4. New quantity (Q2): 270 cups/day

Example 1: Coffee Shop Price Change

  1. % ΔQ = (Q2 - Q1) / ((Q2 + Q1)/2) × 100
  2. % ΔQ = (270 - 300) / ((270 + 300)/2) × 100
  3. % ΔQ = -30 / 285 × 100
  4. % ΔQ = -10.53%

Example 1: Coffee Shop Price Change

  1. % ΔP = (P2 - P1) / ((P2 + P1)/2) × 100
  2. % ΔP = (5.00 - 4.50) / ((5.00 + 4.50)/2) × 100
  3. % ΔP = 0.50 / 4.75 × 100
  4. % ΔP = 10.53%

Example 1: Coffee Shop Price Change

  1. PED = |% ΔQ / % ΔP|
  2. PED = |-10.53% / 10.53%|

PED = 1.0

Example 1: Coffee Shop Price Change

  1. Old revenue: $4.50 × 300 = $1,350/day
  2. New revenue: $5.00 × 270 = $1,350/day
  3. Change: $0 (unit elastic means revenue unchanged)

Example 2: Electronics Store Sale

  1. Original price: $1,200
  2. Sale price: $900
  3. Original sales: 20 units/month
  4. Sale period sales: 45 units/month

Example 2: Electronics Store Sale

  1. % ΔQ = (45 - 20) / ((45 + 20)/2) × 100 = 76.92%
  2. % ΔP = (900 - 1200) / ((900 + 1200)/2) × 100 = -28.57%
  3. PED = |76.92% / -28.57%|

PED = 2.69 (Elastic)

Example 2: Electronics Store Sale

  1. Old revenue: $1,200 × 20 = $24,000
  2. Sale revenue: $900 × 45 = $40,500
  3. Increase: $16,500 (+68.75%)

Example 3: Petrol Price Increase

  1. Price rises from $2.20 to $2.50 per litre
  2. Weekly sales drop from 50,000L to 48,000L

Example 3: Petrol Price Increase

  1. % ΔQ = (48,000 - 50,000) / 49,000 × 100 = -4.08%
  2. % ΔP = (2.50 - 2.20) / 2.35 × 100 = 12.77%
  3. PED = |-4.08% / 12.77%|

PED = 0.32 (Inelastic)

Example 3: Petrol Price Increase

  1. Old revenue: $2.20 × 50,000 = $110,000
  2. New revenue: $2.50 × 48,000 = $120,000
  3. Increase: $10,000 (+9.1%)

Testing Price Changes Safely

  1. 1. Select two similar customer groups
  2. 2. Keep price same for Group A (control)
  3. 3. Change price for Group B (test)
  4. 4. Compare demand changes
  5. 5. Calculate PED from results

Testing Price Changes Safely

  1. 1. Make small price change (5-10%)
  2. 2. Monitor demand for 2-4 weeks
  3. 3. Calculate PED
  4. 4. If profitable, continue; if not, revert

🌍 Real-World Price Elasticity Examples

  1. Old price: $14.99/month
  2. New price: $16.99/month (13.3% increase)
  3. Subscribers before: 850,000
  4. Subscribers after: 810,000

🌍 Real-World Price Elasticity Examples

  1. % ΔQ = (810k - 850k) / 830k × 100 = -4.82%
  2. % ΔP = (16.99 - 14.99) / 15.99 × 100 = 12.51%
  3. PED = |-4.82% / 12.51%|

PED = 0.39 (Inelastic)

🌍 Real-World Price Elasticity Examples

  1. Price increase: $180 → $220 (22% increase)
  2. Weekly bookings drop: 1,200 → 1,140 (5% decrease)
  3. PED = 5% / 22% = 0.23 (Very inelastic)
  1. Price increase: $150 → $190 (26.7% increase)
  2. Weekly bookings drop: 800 → 600 (25% decrease)
  3. PED = 25% / 26.7% = 0.94 (Nearly unit elastic)
  1. Price: $5.50 → $6.50
  2. Daily sales: 200 → 140 loaves
  3. % ΔQ = -30%, % ΔP = 18.2%
  4. PED = 1.65 (Elastic)
  1. Price: $2.00 → $2.30
  2. Daily sales: 1,000 → 950 loaves
  3. % ΔQ = -5.1%, % ΔP = 14.3%
  4. PED = 0.36 (Inelastic)
  1. Price drop: $65 → $49/month
  2. Memberships increase: 400 → 580
  3. % ΔQ = +45%, % ΔP = -24.6%
  4. PED = 1.83 (Elastic)
  5. Revenue: $26,000 → $28,420 (+9.3%)
  1. Price increase: $65 → $75/month
  2. Memberships decrease: 400 → 360
  3. % ΔQ = -10%, % ΔP = 14.3%
  4. PED = 0.70 (Inelastic but close to 1)
  5. Revenue: $26,000 → $27,000 (+3.8%)

Cashflow Management Guide - NZ Personal Finance

What is Cashflow?

  1. Net Cashflow = Total Cash Received - Total Cash Paid Out
  2. Measured over a specific period (week, month, quarter, year)

What is Cashflow?

  1. This month: Income $5,000, Expenses $4,200
  2. Net cashflow: $5,000 - $4,200 = +$800 (positive)
  3. Next month: Income $5,000, Expenses $5,800 (rates due!)
  4. Net cashflow: $5,000 - $5,800 = -$800 (negative)

Why Cashflow ≠ Income

  1. Person A: Income $90,000/year
  2. After tax: $67,275 ($5,606/month)
  3. Expenses: $5,800/month
  4. Monthly cashflow: -$194 (negative!)
  5. Annual cashflow: -$2,325
  6. Result: Good income, but going backwards $2,325/year

Why Cashflow ≠ Income

  1. Person B: Income $55,000/year
  2. After tax: $44,355 ($3,696/month)
  3. Expenses: $3,200/month
  4. Monthly cashflow: +$496 (positive!)
  5. Annual cashflow: +$5,952
  6. Result: Lower income, but saving $5,952/year

The Timing Mismatch Problem

  1. Income: $2,500 every fortnight (26 pays/year)
  2. Rent: $550/week
  3. Other expenses: $350/week
  4. Total weekly outflow: $900
  5. Week 1: +$2,500 in, -$900 out = +$1,600
  6. Week 2: $0 in, -$900 out = -$900
  7. Week 3: +$2,500 in, -$900 out = +$1,600
  8. Week 4: $0 in, -$900 out = -$900

Cashflow vs Profit (Business Context)

  1. Invoice customer: $10,000
  2. Customer pays in 60 days (profit now, cash later)
  3. Meanwhile: rent due, materials to buy, staff to pay
  4. Profit: $10,000 - $6,000 costs = $4,000 (profitable!)
  5. Cashflow: $0 in, $6,000 out = -$6,000 (broke!)

Method 1: Simple Weekly Cashflow Tracker

  1. Salary (after tax): $2,400 fortnightly
  2. Convert to weekly: $2,400 ÷ 2 = $1,200/week average
  3. Partner's income: $800/week
  4. Government support (if any): $150/week
  5. Other income: $50/week
  6. Total weekly income: $2,200
  1. Total income: $2,200/week
  2. Fixed expenses: $673/week
  3. Variable expenses: $735/week
  4. Total expenses: $1,408/week
  5. Net cashflow: $2,200 - $1,408 = +$792/week
  6. Annual surplus: $792 × 52 = $41,184

Common NZ Cashflow Pressure Points

  1. Average NZ rates: $3,000-$4,500/year
  2. Due: July or spread over quarterly instalments
  3. Cashflow impact: $3,500 hit in one month
  4. Solution: Save $292/month year-round

Common NZ Cashflow Pressure Points

  1. Car insurance: $1,200 (renewal March)
  2. House insurance: $1,800 (renewal March)
  3. Contents insurance: $600 (renewal March)
  4. Total hit: $3,600 in one month!
  5. Solution: Save $300/month or stagger renewal dates

Common NZ Cashflow Pressure Points

  1. Per child (state school):
  2. Start of year: Uniform $150, stationery $80, fees $200 = $430
  3. Mid-year: Activities $150, camp $180 = $330
  4. 2 kids: $1,520 annual impact
  5. Solution: Save $130/month year-round

Common NZ Cashflow Pressure Points

  1. Annual rego: $150-$200
  2. WOF: $60-$80
  3. Plus repairs if WOF fails: $200-$800
  4. Unexpected: tyres $600, battery $200
  5. Solution: Vehicle maintenance fund $80/month

Common NZ Cashflow Pressure Points

  1. Summer power: $150/month
  2. Winter power: $350/month
  3. Difference: $200/month extra June-August
  4. 3-month hit: $600 extra
  5. Solution: Average billing or save $50/month summer

Common NZ Cashflow Pressure Points

  1. Gifts: $800
  2. Food/entertaining: $500
  3. Travel: $1,000
  4. Total: $2,300
  5. Solution: Save $190/month from January

🌍 Real-World NZ Cashflow Scenarios

  1. Rent: $550/week = $2,383/month
  2. Power: $180
  3. Internet: $85
  4. Phone: $45
  5. Groceries: $600
  6. Transport (bus): $150
  7. Insurance (monthly allocation): $140
  8. Subscriptions: $35
  9. Eating out: $250
  10. Entertainment: $150
  11. Personal care: $80
  12. Clothing: $100
  13. Miscellaneous: $120
  14. Total: $4,318/month

🌍 Real-World NZ Cashflow Scenarios

  1. Income: $4,866
  2. Expenses: $4,318
  3. Net cashflow: +$548/month
  4. Annual surplus: $6,576
  1. Rent: $2,800
  2. Car payment: $520
  3. Insurance: $320
  4. Internet/phone: $150
  5. ACC levy: $250
  6. Tax (set aside 30%): $3,000 average
  7. Fixed total: $7,040/month
  1. Groceries: $800
  2. Petrol: $400
  3. Power: $250
  4. Other: $500
  5. Variable total: $1,950/month
  1. Income received: $0 (payment lag)
  2. Expenses due: $8,990
  3. Shortfall: -$8,990
  4. Without buffer: Would need credit card/overdraft
  1. 2023: $7,859 - $7,200 = +$659/month surplus
  2. Saving: $7,908/year
  3. 2024: $7,859 - $8,350 = -$491/month deficit!
  4. Going backwards: -$5,892/year
  5. Swing: $13,800/year worse off
  1. Cut expenses: $620/month
  2. Increased income: $700/month
  3. Total improvement: $1,320/month
  4. New cashflow: -$491 + $1,320 = +$829/month
  5. Back to positive, saving $9,948/year
  1. Profit: $93,000
  2. Income tax (33%): $30,690
  3. ACC levy: $1,800
  4. Available for living: $60,510
  5. Monthly average: $5,043

CAPM Guide - Capital Asset Pricing Model

The CAPM Formula

  1. Expected Return = Risk-Free Rate + Beta × (Market Return - Risk-Free Rate)
  2. or more simply:
  3. Expected Return = Risk-Free Rate + Beta × Market Risk Premium

Component 4: Market Risk Premium

  1. Market Risk Premium = Market Return - Risk-Free Rate
  2. Example: 10% - 4% = 6% market risk premium

Simple Example

  1. Risk-free rate (NZ government bonds): 4%
  2. Market return (NZX 50 historical average): 9%
  3. Beta of the tech stock: 1.3
  4. CAPM Calculation:
  5. Expected Return = 4% + 1.3 × (9% - 4%)
  6. Expected Return = 4% + 1.3 × 5%
  7. Expected Return = 4% + 6.5%

Expected Return = 10.5%

Example 1: Basic CAPM Calculation

  1. Risk-free rate (NZ 10-year bonds): 4.2%
  2. Expected market return (NZX 50): 8.5%
  3. Fisher & Paykel beta: 0.85

Example 1: Basic CAPM Calculation

  1. Market Risk Premium = Market Return - Risk-Free Rate
  2. = 8.5% - 4.2%

= 4.3%

Example 1: Basic CAPM Calculation

  1. Expected Return = Risk-Free Rate + Beta × Market Risk Premium
  2. = 4.2% + 0.85 × 4.3%
  3. = 4.2% + 3.66%

= 7.86%

Example 2: High-Beta Tech Stock

  1. Risk-free rate: 3.5%
  2. Market return: 10%
  3. Tech stock beta: 1.8

Example 2: High-Beta Tech Stock

  1. Expected Return = 3.5% + 1.8 × (10% - 3.5%)
  2. = 3.5% + 1.8 × 6.5%
  3. = 3.5% + 11.7%

= 15.2%

Example 3: Defensive Stock (Low Beta)

  1. Risk-free rate: 4%
  2. Market return: 9%
  3. Utility company beta: 0.6

Example 3: Defensive Stock (Low Beta)

  1. Expected Return = 4% + 0.6 × (9% - 4%)
  2. = 4% + 0.6 × 5%
  3. = 4% + 3%

= 7%

Using CAPM for Investment Decisions

  1. Stock Beta: 1.2
  2. CAPM Expected Return: 4% + 1.2(9% - 4%) = 10%
  3. Stock's Actual Forecast Return: 12%

Decision: Consider buying (12% > 10%)

🌍 Real-World Examples

  1. NZ 10-year government bond yield (risk-free rate): 4.5%
  2. NZX 50 historical return (market return): 8.8%
  3. Market risk premium: 8.8% - 4.5% = 4.3%

🌍 Real-World Examples

  1. Beta: 0.9
  2. Analyst forecast return: 7.5%
  3. CAPM Expected Return:
  4. = 4.5% + 0.9 × 4.3%
  5. = 4.5% + 3.87%

= 8.37%

🌍 Real-World Examples

  1. Beta: 1.6
  2. Analyst forecast return: 12%
  3. CAPM Expected Return:
  4. = 4.5% + 1.6 × 4.3%
  5. = 4.5% + 6.88%

= 11.38%

  1. Risk-free rate: 4%
  2. Market return: 10%
  3. Market risk premium: 6%
  1. 30% Defensive Stocks (8.2% return) = $15,000
  2. 50% Market Index Fund (10% return) = $25,000
  3. 20% Growth Stocks (12.4% return) = $10,000
  1. (0.30 × 8.2%) + (0.50 × 10%) + (0.20 × 12.4%)
  2. = 2.46% + 5% + 2.48%

= 9.94%

  1. (0.30 × 0.7) + (0.50 × 1.0) + (0.20 × 1.4)
  2. = 0.21 + 0.50 + 0.28

= 0.99

  1. Company: Manufacturing Ltd
  2. Industry beta: 1.1
  3. Risk-free rate (NZ 10-year bonds): 4.3%
  4. Expected market return (NZX 50): 9.2%
  1. Cost of Equity = 4.3% + 1.1 × (9.2% - 4.3%)
  2. = 4.3% + 1.1 × 4.9%
  3. = 4.3% + 5.39%

= 9.69%

  1. Return on investment: $250,000 / $2,000,000 = 12.5%
  2. Cost of equity (hurdle rate): 9.69%
  3. 12.5% > 9.69%

Decision: Proceed with expansion

Profit Margin Guide

The Basic Formula

  1. Profit Margin % = (Selling Price - Cost Price) / Selling Price × 100
  2. Or:
  3. Profit Margin % = Profit / Revenue × 100

Simple Example

  1. Buy product for: $60
  2. Sell product for: $100
  3. Profit: $40
  4. Profit Margin = ($100 - $60) / $100 × 100
  5. = $40 / $100 × 100

Profit Margin = 40%

Types of Profit Margins

  1. Revenue: $1,000,000
  2. COGS (Cost of Goods Sold): $400,000
  3. Gross Profit: $600,000 (60% gross margin)
  4. Operating Expenses: $350,000
  5. Operating Profit: $250,000 (25% operating margin)
  6. Interest & Tax: $100,000
  7. Net Profit: $150,000 (15% net margin)

Profit Margin vs Markup

  1. Cost: $50, Selling Price: $100, Profit: $50
  2. Margin = $50 / $100 = 50%
  3. Markup = $50 / $50 = 100%
  4. Same $50 profit, different percentages!

Basic Calculation Example

  1. Wholesale cost: $40
  2. Retail price: $79.99
  3. Profit = $79.99 - $40 = $39.99
  4. Margin % = $39.99 / $79.99 × 100

Margin = 50%

Working Backwards: Find Selling Price

  1. Margin = (Price - Cost) / Price
  2. 0.60 = (Price - $30) / Price
  3. 0.60 × Price = Price - $30
  4. $30 = Price - 0.60 × Price
  5. $30 = 0.40 × Price
  6. Price = $30 / 0.40

Price = $75

Working Backwards: Find Selling Price

  1. Selling Price = Cost / (1 - Desired Margin %)
  2. = $30 / (1 - 0.60)
  3. = $30 / 0.40 = $75

Margin Improvement Strategies

  1. Revenue: $100,000
  2. Profit: $40,000

Margin Improvement Strategies

  1. New price: $110, Volume: 950 units
  2. Revenue: $104,500
  3. Cost: $60 × 950 = $57,000
  4. Profit: $47,500
  5. Margin: 45.5%
  6. Profit increase: $7,500 (18.75%)

Margin Improvement Strategies

  1. Price: $100, New cost: $54, Volume: 1,000
  2. Revenue: $100,000
  3. Cost: $54,000
  4. Profit: $46,000
  5. Margin: 46%
  6. Profit increase: $6,000 (15%)

Margin Improvement Strategies

  1. Premium: $340,000 (50% margin) = $170,000 profit
  2. Standard: $500,000 (35% margin) = $175,000 profit
  3. Budget: $160,000 (15% margin) = $24,000 profit
  4. Total profit: $369,000
  5. Overall margin: 36.9%
  6. Profit increase: $14,000 (3.9%)

Volume vs Margin Trade-off

  1. Price: $150, Cost: $60, Volume: 500
  2. Margin: 60%
  3. Revenue: $75,000
  4. Profit: $45,000

Volume vs Margin Trade-off

  1. Price: $90, Cost: $60, Volume: 1,500
  2. Margin: 33%
  3. Revenue: $135,000
  4. Profit: $45,000

Breakeven Analysis

  1. Contribution margin per unit = $50 - $20 = $30
  2. Breakeven units = Fixed costs / Contribution margin
  3. = $50,000 / $30

= 1,667 units to break even

🌍 Real-World Profit Margin Examples

  1. Selling price: $5.00
  2. Coffee beans: $0.40
  3. Milk: $0.35
  4. Cup/lid: $0.25
  5. Total cost: $1.00
  6. Gross margin: 80%

🌍 Real-World Profit Margin Examples

  1. Selling price: $12.00
  2. Ingredients: $4.50
  3. Packaging: $0.50
  4. Total cost: $5.00
  5. Gross margin: 58%

🌍 Real-World Profit Margin Examples

  1. Gross profit: $1,757
  2. Labor (2 staff × 8hr × $25): $400
  3. Rent (daily): $200
  4. Utilities, other: $100
  5. Net profit: $1,057
  6. Net margin: 43%
  1. Revenue per customer: $99
  2. Hosting costs: $5
  3. Support (allocated): $4
  4. COGS: $9
  5. Gross margin: 91%
  1. Gross margin: 25%
  2. Net margin: 2%
  3. Annual revenue: $500M
  4. Net profit: $10M
  5. Strategy: High volume, low margins
  1. Gross margin: 65%
  2. Net margin: 18%
  3. Annual revenue: $5M
  4. Net profit: $900k
  5. Strategy: Low volume, high margins

Price Elasticity of Supply Guide

The PES Formula (Midpoint Method)

  1. PES = (% Change in Quantity Supplied) / (% Change in Price)
  2. Using midpoint method:
  3. PES = [(Q2 - Q1) / ((Q2 + Q1)/2)] / [(P2 - P1) / ((P2 + P1)/2)]

Simple Example

  1. % Change Quantity = (11,500 - 10,000) / 10,750 = 14.0%
  2. % Change Price = (240 - 200) / 220 = 18.2%
  3. PES = 14.0% / 18.2%

PES = 0.77 (Inelastic)

Example 1: Coffee Shop Staffing

  1. Wage: $22/hour → $25/hour
  2. Workers willing to work: 12 → 16
  3. % Change Quantity = (16 - 12) / 14 = 28.6%
  4. % Change Price = (25 - 22) / 23.5 = 12.8%
  5. PES = 28.6% / 12.8%

PES = 2.23 (Elastic)

Example 2: Commercial Property Development

  1. Office rent: $500 → $650 per m²/year
  2. Available space: 100,000 → 102,000 m²
  3. PES = 0.12 (Highly inelastic)
  4. Can't build new buildings in 6 months

Example 2: Commercial Property Development

  1. Same rent increase
  2. Available space: 100,000 → 125,000 m²
  3. PES = 1.45 (Elastic)
  4. New buildings completed, supply responds

Example 3: Agricultural Production

  1. Milk price: $0.50 → $0.70 per litre
  2. Weekly supply: 1M → 1.1M litres
  3. % Change Quantity = (1.1 - 1.0) / 1.05 = 9.5%
  4. % Change Price = (0.70 - 0.50) / 0.60 = 33.3%
  5. PES = 9.5% / 33.3%

PES = 0.29 (Inelastic)

Market Equilibrium Impact

  1. Demand ↑ 20%
  2. Price rises only 8%
  3. Quantity increases 16%
  4. Result: Modest price increase, big quantity increase

Market Equilibrium Impact

  1. Demand ↑ 20%
  2. Price rises 18%
  3. Quantity increases only 5%
  4. Result: Large price spike, small quantity increase

Tax Burden and Elasticity

  1. Example: Tax on professional sports tickets
  2. Supply: Fixed (stadium capacity) PES = 0.1
  3. Demand: Flexible (entertainment options) PED = 2.0
  4. Result: Sellers bear 95% of tax
  5. Can't increase supply, must absorb tax

Tax Burden and Elasticity

  1. Example: Tax on gasoline
  2. Supply: Flexible (refineries adjust) PES = 1.5
  3. Demand: Inflexible (must drive) PED = 0.3
  4. Result: Buyers bear 80% of tax
  5. Suppliers pass costs to consumers

🌍 Real-World Supply Elasticity Examples

  1. Price: $2 → $8 per mask (300% increase)
  2. Global supply: 50M → 60M per day (20% increase)
  3. PES = 20% / 300% = 0.07
  4. Nearly perfectly inelastic

🌍 Real-World Supply Elasticity Examples

  1. Price stabilized: $3 per mask
  2. Supply: 200M per day (300% increase from baseline)
  3. PES = 1.5 (now elastic)
  4. Factories converted, new producers entered

🌍 Real-World Supply Elasticity Examples

  1. Average price: $800k → $1.2M (50% increase)
  2. Dwellings: 500,000 → 510,000 (2% increase)
  3. PES = 0.04 (extremely inelastic)

🌍 Real-World Supply Elasticity Examples

  1. Average fare: $20
  2. Drivers active: 500

🌍 Real-World Supply Elasticity Examples

  1. Surge fare: $50 (150% increase)
  2. Drivers active: 1,200 (140% increase)
  3. PES = 140% / 150% = 0.93
  1. Developer salary: $100k → $130k (30% increase)
  2. Team size: 50 → 52 developers (4% increase)
  3. PES = 0.13 (very inelastic)
  4. Reason: Can only hire immediately available talent
  1. Same salary increase
  2. Team size: 50 → 65 developers (30% increase)
  3. PES = 1.0 (unit elastic)
  4. Reason: Recruited nationally, trained juniors
  1. Same salary level maintained
  2. Team size: 50 → 85 developers (70% increase)
  3. PES = 2.33 (elastic)
  4. Reason: Offshore teams, coding bootcamp graduates, automation tools

Gross Margin Guide

The Gross Margin Formula

  1. Gross Margin % = ((Revenue - COGS) / Revenue) × 100
  2. Or:
  3. Gross Margin % = (Gross Profit / Revenue) × 100

Simple Example

  1. You sell a product for: $100
  2. Cost to make/buy it (COGS): $40
  3. Gross Profit = $100 - $40 = $60
  4. Gross Margin = ($60 / $100) × 100

= 60%

Gross Margin vs Net Profit Margin

  1. Revenue: $1,000,000
  2. COGS: $400,000
  3. Gross Profit: $600,000 (60% gross margin)
  4. Operating Expenses: $450,000
  5. Interest: $20,000
  6. Taxes: $39,000
  7. Net Income: $91,000 (9.1% net profit margin)

Detailed Calculation Examples

  1. Project revenue: $50,000
  2. Designer hours: 200 at $35/hour = $7,000
  3. Developer hours: 150 at $45/hour = $6,750
  4. Stock photos/fonts: $500
  5. Total COGS: $14,250
  6. Gross Profit = $50,000 - $14,250 = $35,750
  7. Gross Margin = ($35,750 / $50,000) × 100

= 71.5%

Four Ways to Improve Gross Margin

  1. Selling price: $50
  2. COGS: $30
  3. Gross margin: 40%

Four Ways to Improve Gross Margin

  1. New selling price: $55
  2. COGS: $30 (unchanged)
  3. New gross profit: $25
  4. New gross margin: 45.5%

Four Ways to Improve Gross Margin

  1. Selling price: $50
  2. Old COGS: $30
  3. New COGS after negotiation: $27 (10% reduction)
  4. Old gross margin: 40%
  5. New gross margin: 46%

Four Ways to Improve Gross Margin

  1. Product A: $100,000 revenue, 15% margin
  2. Product B: $80,000 revenue, 55% margin
  3. Overall margin: 32.8%
  4. Drop Product A, focus on Product B:
  5. Revenue decreases 44% BUT
  6. Gross margin jumps to 55%
  7. Can grow Product B to offset revenue loss

The Margin-Volume Trade-Off

  1. Price: $100
  2. COGS: $30
  3. Gross margin: 70%
  4. Units sold: 1,000
  5. Total gross profit: $70,000

The Margin-Volume Trade-Off

  1. Price: $70 (30% discount)
  2. COGS: $30
  3. Gross margin: 57%
  4. Units sold: 2,000 (doubled)
  5. Total gross profit: $80,000

🌍 Real-World Gross Margin Examples

  1. Flat whites sold: 150 × $4.20 profit = $630
  2. Muffins sold: 45 × $3.30 profit = $148.50
  3. Sandwiches sold: 60 × $5.50 profit = $330
  4. Smoothies sold: 30 × $5.00 profit = $150
  5. Total daily gross profit: $1,258.50

🌍 Real-World Gross Margin Examples

  1. Selling price: $120
  2. COGS (product + shipping): $45
  3. Gross profit per unit: $75
  4. Gross margin: 62.5%
  5. Expected monthly sales: 200 units
  6. Monthly gross profit: $15,000
  1. Selling price: $89
  2. COGS: $45
  3. Gross profit per unit: $44
  4. Gross margin: 49.4%
  5. Expected monthly sales: 400 units
  6. Monthly gross profit: $17,600
  1. Selling price: $500
  2. Current COGS breakdown:
  3. - Raw materials: $180
  4. - Direct labor: $90
  5. - Packaging: $30
  6. Total COGS: $300
  7. Gross margin: 40%
  8. Monthly production: 500 units
  9. Monthly gross profit: $100,000
  1. Selling price: $500 (unchanged)
  2. New COGS: $265
  3. New gross margin: 47%
  4. Monthly gross profit: $117,500
  5. Improvement: $17,500/month extra profit
  1. Project fee: $100,000
  2. Consultant hours: 800 at $50/hour = $40,000
  3. Gross margin: 60%
  1. Project fee: $100,000 (can't easily raise due to contracts)
  2. Consultant rate increased to $60/hour (20% raise)
  3. Same 800 hours = $48,000 COGS
  4. New gross margin: 52%
  5. Margin compression: 8 percentage points!

IRR Guide

The IRR Concept

  1. NPV = 0
  2. Or expanded:
  3. Initial Investment = Present Value of Future Cash Flows

Simple Example

  1. Year 0: -$10,000 (investment)
  2. Year 1: +$4,000
  3. Year 2: +$5,000
  4. Year 3: +$4,000
  5. IRR = 13.7%

Example: Equipment Purchase

  1. NPV = -$150,000 + $30,000/1.10 + $35,000/1.10² + ... + $85,000/1.10⁵
  2. NPV = -$150,000 + $27,273 + $28,926 + $33,808 + $40,980 + $52,775
  3. NPV = $33,762 (positive, so IRR > 10%)

Example: Equipment Purchase

  1. NPV = -$150,000 + $30,000/1.18 + $35,000/1.18² + ... + $85,000/1.18⁵
  2. NPV = -$1,458 (slightly negative, so IRR < 18%)

Using Excel (Much Easier)

  1. In Excel, list cash flows in column A (A1 to A6)
  2. A1: -150000
  3. A2: 30000
  4. A3: 35000
  5. A4: 45000
  6. A5: 60000
  7. A6: 85000
  8. In cell B1, enter: =IRR(A1:A6)

Result: 17.02%

🌍 Real-World IRR Applications

  1. Initial investment: $400,000 (buildout, equipment, inventory)
  2. Year 1 net cash flow: $60,000
  3. Year 2: $85,000 (growing reputation)
  4. Year 3: $110,000
  5. Year 4: $125,000
  6. Year 5: $140,000
  7. Residual value Year 5: $200,000 (sell or refinance)

🌍 Real-World IRR Applications

  1. Year 0: -$400,000
  2. Year 1-4: Cash flows as above
  3. Year 5: $140,000 + $200,000 = $340,000
  4. IRR = 21.3%

🌍 Real-World IRR Applications

  1. Owner's hurdle rate: 18% (reflects risk and opportunity cost)
  2. IRR of 21.3% exceeds 18%

Decision: Proceed with expansion

🌍 Real-World IRR Applications

  1. Purchase price: $550,000
  2. Down payment (20%): $110,000
  3. Annual net rental income (after mortgage): $8,500
  4. Hold for 10 years
  5. Expected appreciation: 3% annually
  6. Selling price Year 10: $739,000
  7. Less loan balance: -$310,000
  8. Less selling costs (6%): -$44,000
  9. Net proceeds: $385,000

🌍 Real-World IRR Applications

  1. Year 0: -$110,000 (down payment)
  2. Years 1-10: $8,500 annually
  3. Year 10 additional: $385,000 (sale proceeds)
  4. Total Year 10: $393,500
  5. IRR = 11.8%
  1. Purchase price: $50M
  2. Equity invested: $15M (30%)
  3. Debt: $35M (70%)
  4. Hold period: 5 years
  1. EBITDA: $12M
  2. Exit multiple: 7x EBITDA
  3. Enterprise value: $84M
  4. Less debt: -$28M (paid down from $35M)
  5. Equity value: $56M
  1. Year 0: -$15M
  2. Year 1-5: Annual cash flows as above
  3. Year 5 exit: $56M + $3M cash flow = $59M
  4. IRR = 32.1%
  1. Investment: $10,000
  2. Year 1 return: $13,000
  3. IRR = 30%
  4. NPV at 10% = $1,818
  1. Investment: $100,000
  2. Year 1: $30,000
  3. Year 2: $50,000
  4. Year 3: $60,000
  5. IRR = 18%
  6. NPV at 10% = $18,882

EBITDA Guide

The EBITDA Formula

  1. EBITDA = Revenue - COGS - Operating Expenses (excluding D&A)
  2. Or starting from net income:
  3. EBITDA = Net Income + Interest + Taxes + Depreciation + Amortization

Simple Example

  1. Revenue: $1,000,000
  2. Cost of Goods Sold: $400,000
  3. Gross Profit: $600,000
  4. Operating Expenses (cash):
  5. Rent: $60,000
  6. Salaries: $280,000
  7. Utilities: $20,000
  8. Other: $40,000
  9. Cash Operating Expenses: $400,000
  10. Non-Cash Expenses (added back for EBITDA):
  11. Depreciation: $35,000
  12. Amortization: $15,000
  13. EBITDA = $600,000 - $400,000

EBITDA = $200,000

Method 1: Top-Down from Revenue

  1. Revenue: $5,000,000
  2. Cost of Goods Sold: $2,000,000
  3. Gross Profit: $3,000,000

Method 1: Top-Down from Revenue

  1. EBITDA = Gross Profit - Cash Operating Expenses
  2. EBITDA = $3,000,000 - $2,000,000

EBITDA = $1,000,000

Method 2: Bottom-Up from Net Income

  1. Net Income: $450,000
  2. Add back: Income Tax ($150,000)
  3. Add back: Interest Expense ($100,000)
  4. Add back: Depreciation ($250,000)
  5. Add back: Amortization ($50,000)
  6. EBITDA = $450,000 + $150,000 + $100,000 + $250,000 + $50,000

EBITDA = $1,000,000

EBITDA Margin

  1. EBITDA Margin = (EBITDA / Revenue) × 100
  2. For ManufactureCo:
  3. EBITDA Margin = ($1,000,000 / $5,000,000) × 100

= 20%

Adjusted EBITDA

  1. EBITDA: $1,000,000
  2. Add back: Restructuring costs ($80,000 one-time)
  3. Add back: Legal settlement ($50,000 unusual)
  4. Add back: Loss on asset sale ($20,000)
  5. Adjusted EBITDA: $1,150,000

🌍 Real-World EBITDA Applications

  1. Revenue: $800,000,000
  2. COGS: $320,000,000
  3. Operating Expenses (cash): $240,000,000
  4. Depreciation: $120,000,000 (huge network infrastructure)
  5. Amortization: $20,000,000 (spectrum licenses)
  6. Interest: $30,000,000
  7. Taxes: $21,000,000

🌍 Real-World EBITDA Applications

  1. Industry EBITDA multiple for telecom: 8x
  2. Enterprise Value = $240M × 8

= $1,920,000,000 (≈$1.92 billion)

🌍 Real-World EBITDA Applications

  1. Revenue: $12,000,000
  2. Food costs (COGS): $3,600,000 (30%)
  3. Labor: $4,200,000
  4. Rent: $1,800,000
  5. Other operating: $900,000
  6. Depreciation: $360,000 (equipment, furniture)
  7. Interest: $180,000
  8. EBITDA = $12M - $3.6M - $4.2M - $1.8M - $0.9M

EBITDA = $1,500,000

  1. Annual Interest Payments: $180,000
  2. Interest Coverage = EBITDA / Interest
  3. = $1,500,000 / $180,000

= 8.3x coverage (very healthy)

  1. EBITDA: $4,000,000
  2. Purchase Price: 6x EBITDA = $24,000,000
  3. Down Payment (equity): $6,000,000
  4. Debt Financing: $18,000,000
  5. Interest Rate: 6% = $1,080,000/year
  1. EBITDA: $4,000,000
  2. Interest Coverage = $4,000,000 / $1,080,000

= 3.7x (healthy coverage)

  1. Improve EBITDA to $6M over 5 years (50% growth)
  2. Exit at 6x EBITDA = $36M
  3. Repay debt: -$12M (paid down $6M over 5 years)
  4. Net proceeds: $24M
  5. Initial equity: $6M
  6. Return: 4x equity in 5 years (≈32% IRR)

EBIT Guide - Earnings Before Interest and Tax

The EBIT Formula

  1. EBIT = Revenue - Cost of Goods Sold - Operating Expenses
  2. Or alternatively:
  3. EBIT = Net Income + Interest + Taxes

Simple Example

  1. Revenue: $500,000
  2. Cost of Goods Sold (COGS): $200,000
  3. Gross Profit: $300,000
  4. Operating Expenses:
  5. Rent: $30,000
  6. Salaries: $120,000
  7. Utilities: $10,000
  8. Supplies: $5,000
  9. Vehicle: $8,000
  10. Total Operating Expenses: $173,000
  11. EBIT = $300,000 - $173,000

EBIT = $127,000

Detailed EBIT Calculation Example

  1. Sales revenue: $800,000
  2. Returns and discounts: ($20,000)
  3. Net Revenue: $780,000

Detailed EBIT Calculation Example

  1. Inventory purchases: $320,000
  2. Freight and shipping: $15,000
  3. Total COGS: $335,000

Detailed EBIT Calculation Example

  1. EBIT = Gross Profit - Operating Expenses
  2. EBIT = $445,000 - $348,000

EBIT = $97,000

EBIT Margin

  1. EBIT Margin = (EBIT / Revenue) × 100
  2. For RetailCo:
  3. EBIT Margin = ($97,000 / $780,000) × 100

= 12.4%

Using EBIT for Decision Making

  1. Current EBIT: $97,000
  2. Estimated new location EBIT: $45,000
  3. Combined EBIT: $142,000
  4. Improvement: +46% increase in operating profit

🌍 Real-World EBIT Applications

  1. Revenue: $2,000,000
  2. COGS: $400,000
  3. Operating Expenses: $1,100,000
  4. EBIT: $500,000
  5. Interest Expense: $150,000 (lots of debt)
  6. Tax: $105,000
  7. Net Income: $245,000

🌍 Real-World EBIT Applications

  1. Revenue: $1,800,000
  2. COGS: $350,000
  3. Operating Expenses: $1,000,000
  4. EBIT: $450,000
  5. Interest Expense: $20,000 (minimal debt)
  6. Tax: $129,000
  7. Net Income: $301,000
  1. Revenue (consulting fees): $1,200,000
  2. COGS: $0 (service business, no physical products)
  3. Gross Profit: $1,200,000
  4. Operating Expenses:
  5. Employee salaries: $680,000
  6. Office rent: $85,000
  7. Technology/software: $45,000
  8. Travel: $75,000
  9. Marketing: $40,000
  10. Other expenses: $35,000
  11. Total Operating Expenses: $960,000
  12. EBIT = $1,200,000 - $960,000

EBIT = $240,000

  1. Revenue: $180,000
  2. COGS: $95,000
  3. Gross Profit: $85,000
  4. Operating Expenses: $145,000
  5. EBIT = $85,000 - $145,000

EBIT = -$60,000 (loss)

  1. To reach break-even EBIT ($0):
  2. Need to increase gross profit by $60,000
  3. At current 47% gross margin ($85k/$180k)
  4. Would need revenue of ~$310,000
  5. Or reduce operating expenses to $85,000

NPV Guide - Net Present Value

The NPV Formula

  1. NPV = Σ [CFt / (1 + r)^t] - Initial Investment
  2. Where:
  3. CFt = Cash flow in period t
  4. r = Discount rate
  5. t = Time period

Simple Example

  1. Initial investment: $10,000
  2. Year 1 cash flow: $4,000
  3. Year 2 cash flow: $5,000
  4. Year 3 cash flow: $4,000
  5. Discount rate: 10%
  6. PV Year 1: $4,000 / 1.10 = $3,636
  7. PV Year 2: $5,000 / 1.10² = $4,132
  8. PV Year 3: $4,000 / 1.10³ = $3,005
  9. Total PV of inflows: $10,773
  10. NPV = $10,773 - $10,000

NPV = $773

Example: Manufacturing Equipment

  1. Year 1: $30,000 / (1.10)¹ = $27,273
  2. Year 2: $35,000 / (1.10)² = $28,926
  3. Year 3: $45,000 / (1.10)³ = $33,808
  4. Year 4: $60,000 / (1.10)⁴ = $40,981
  5. Year 5: $85,000 / (1.10)⁵ = $52,779

Uneven Cash Flow Example

  1. Year 0: -$200,000
  2. Year 1: -$50,000 / 1.15 = -$43,478
  3. Year 2: $40,000 / 1.15² = $30,246
  4. Year 3: $120,000 / 1.15³ = $78,945
  5. Year 4: $180,000 / 1.15⁴ = $102,941
  6. Year 5: $200,000 / 1.15⁵ = $99,432
  7. Sum of PVs: $68,086

NPV = $68,086

🌍 Real-World NPV Examples

  1. Initial fit-out: $350,000
  2. Equipment: $150,000
  3. Initial inventory: $50,000
  4. Total: $550,000

🌍 Real-World NPV Examples

  1. PV of 10 years cash flows: $685,240
  2. Initial investment: $550,000

NPV = $135,240

🌍 Real-World NPV Examples

  1. System cost: $18,000
  2. Government rebate: -$3,000
  3. Net investment: $15,000

🌍 Real-World NPV Examples

  1. Electricity bill reduction: $2,100/year
  2. Maintenance: -$100/year
  3. Net annual benefit: $2,000
  4. System life: 25 years

🌍 Real-World NPV Examples

  1. PV of 25 years × $2,000 at 5%: $28,199
  2. Initial cost: $15,000

NPV = $13,199

  1. Property price: $600,000
  2. Down payment (30%): $180,000
  3. Renovation: $20,000
  4. Total cash invested: $200,000
  1. Years 1-10: $8,000/year positive
  2. Year 10 sale: $780,000 (30% appreciation)
  3. Less remaining mortgage: -$320,000
  4. Net proceeds Year 10: $460,000
  1. PV of annual $8k: $45,181
  2. PV of Year 10 proceeds: $148,135
  3. Total PV: $193,316
  4. Initial investment: $200,000

NPV = -$6,684

Asset Turnover Ratio Guide

Simple Example

  1. ABC Retail Store
  2. Annual net sales: $500,000
  3. Assets at start of year: $200,000
  4. Assets at end of year: $250,000
  5. Step 1: Calculate Average Assets
  6. ($200,000 + $250,000) ÷ 2 = $225,000
  7. Step 2: Calculate Ratio
  8. $500,000 ÷ $225,000 = 2.22
  9. This means ABC generates $2.22 in sales for every $1 of assets.

Asset Turnover Ratio: 2.22x

High Asset Turnover Ratio

  1. Example: High Ratio (4.0x)
  2. Online retailer with minimal physical assets
  3. Sales: $2,000,000
  4. Average assets: $500,000

Ratio: 4.0x - Very efficient, low asset intensity

Low Asset Turnover Ratio

  1. Example: Low Ratio (0.3x)
  2. Electric utility company
  3. Sales: $300,000,000
  4. Average assets: $1,000,000,000

Ratio: 0.3x - Normal for utilities (massive infrastructure)

🔢 Real-World Examples

  1. Annual sales: $450,000
  2. Beginning assets: $150,000
  3. Ending assets: $170,000
  4. Average assets: ($150,000 + $170,000) ÷ 2 = $160,000

Asset Turnover: $450,000 ÷ $160,000 = 2.81x

🔢 Real-World Examples

  1. Annual sales: $800,000
  2. Beginning assets: $600,000 (expensive roasting equipment)
  3. Ending assets: $650,000
  4. Average assets: ($600,000 + $650,000) ÷ 2 = $625,000

Asset Turnover: $800,000 ÷ $625,000 = 1.28x

  1. Annual sales: $600,000
  2. Total assets: $250,000

Asset Turnover: 2.4x

  1. Projected total sales: $1,100,000 (not quite double)
  2. Projected total assets: $520,000 (new store + inventory)

Projected Turnover: 2.12x

  1. Annual sales: $2,000,000
  2. Average assets: $1,600,000
  3. Large inventory: $400,000
  4. Equipment utilization: 60%

Asset Turnover: 1.25x

  1. Annual sales: $2,200,000 (10% increase)
  2. Average assets: $1,400,000 (reduced!)
  3. Lean inventory: $200,000 (50% reduction)
  4. Equipment utilization: 85%

Asset Turnover: 1.57x

CAGR Explained

Simple Example

  1. Step 1: Divide ending by beginning
  2. $16,000 ÷ $10,000 = 1.6
  3. Step 2: Raise to power of (1 ÷ years)
  4. 1.6 ^ (1 ÷ 5) = 1.6 ^ 0.2 = 1.0986
  5. Step 3: Subtract 1
  6. 1.0986 - 1 = 0.0986
  7. Step 4: Convert to percentage

0.0986 × 100 = 9.86% CAGR

Step-by-Step Calculation

  1. Given:
  2. Beginning Value: $25,000
  3. Ending Value: $34,500
  4. Number of Years: 3
  5. Formula:
  6. CAGR = ($34,500 ÷ $25,000)^(1÷3) - 1
  7. Step 1:
  8. $34,500 ÷ $25,000 = 1.38
  9. Step 2:
  10. 1.38 ^ (1÷3) = 1.38 ^ 0.333 = 1.1135
  11. Step 3:
  12. 1.1135 - 1 = 0.1135

CAGR = 11.35% per year

Step-by-Step Calculation

  1. Given:
  2. Beginning Value (2019): $500,000
  3. Ending Value (2024): $1,200,000
  4. Number of Years: 5
  5. Calculation:
  6. CAGR = ($1,200,000 ÷ $500,000)^(1÷5) - 1
  7. = 2.4 ^ 0.2 - 1
  8. = 1.1914 - 1

CAGR = 19.14% per year

Working Backwards: Using CAGR to Forecast

  1. Future Value = $50,000 × (1 + 0.07)^20
  2. = $50,000 × (1.07)^20
  3. = $50,000 × 3.8697

= $193,485

🌍 Real-World CAGR Examples

  1. Beginning Value (2018): $40,000
  2. Ending Value (2025): $68,500
  3. Time Period: 7 years
  4. CAGR = ($68,500 ÷ $40,000)^(1÷7) - 1
  5. = 1.7125 ^ 0.1429 - 1
  6. = 1.0789 - 1

= 7.89% CAGR

  1. Year 1 (2021): $150,000
  2. Year 2 (2022): $320,000
  3. Year 3 (2023): $580,000
  4. Year 4 (2024): $950,000
  5. Year 5 (2025): $1,400,000
  1. Beginning: $150,000
  2. Ending: $1,400,000
  3. Years: 4 (from 2021 to 2025)
  4. CAGR = ($1,400,000 ÷ $150,000)^(1÷4) - 1
  5. = 9.333 ^ 0.25 - 1

= 74.4% CAGR

  1. Purchased 2015: $650,000
  2. Current Value 2025: $1,050,000
  3. Time: 10 years
  4. CAGR = ($1,050,000 ÷ $650,000)^(1÷10) - 1

= 4.93% CAGR

  1. Purchased 2018: $420,000
  2. Current Value 2025: $580,000
  3. Time: 7 years
  4. CAGR = ($580,000 ÷ $420,000)^(1÷7) - 1

= 4.68% CAGR

Employee Share Schemes Tax

How the Benefit Is Measured

  1. Market value of the shares on the share scheme taxing date
  2. minus any amount you paid for the shares or rights

= your taxable ESS benefit (employment income)

🔢 Worked Examples

  1. Step 1: value the benefit
  2. 400 shares × $25.00 = $10,000 market value
  3. Less amount paid: $0
  4. ESS benefit: $10,000
  5. Step 2: find the marginal rate
  6. Salary $95,000 is in the 33% band ($78,101 to $180,000)
  7. Benefit $10,000 stacks on top: $95,000 to $105,000, still under $180,000
  8. So all $10,000 is taxed at 33%
  9. Step 3: the tax

$10,000 × 33% = $3,300 of income tax

🔢 Worked Examples

  1. Step 1: what he paid
  2. $8.00 × (1 − 0.15) = $6.80 per share
  3. 1,000 × $6.80 = $6,800 paid
  4. Step 2: the benefit (the discount)
  5. Market value: 1,000 × $8.00 = $8,000
  6. Benefit: $8,000 − $6,800 = $1,200
  7. Step 3: the tax
  8. Income $70,000 is in the 30% band; $70,000 + $1,200 = $71,200, still under $78,100

$1,200 × 30% = $360 of income tax

  1. If the value were fixed at grant (2026)
  2. Price then $10.00: 500 × $10.00 = $5,000 (but this is NOT the benefit)
  3. The benefit is measured on the taxing date (2029)
  4. Price then $18.00: 500 × $18.00 = $9,000 market value
  5. Less amount paid: $0

ESS benefit: $9,000, taxed in the year the restrictions lift

  1. Total ESS benefit for the year
  2. RSUs: $10,000
  3. Discount: $2,000
  4. Total: $12,000
  5. Tax at the marginal rate
  6. Salary $85,000 + $12,000 = $97,000, all within the 33% band
  7. $12,000 × 33% = $3,960

Set aside about $3,960 for the year-end bill

Budgeting on an Irregular Income

Two Numbers to Work Out

  1. Add up your essential costs for a typical month
  2. Average your income over the last several months
  3. Set your personal wage at or below that average
  4. Make sure the wage covers at least your essential costs

In a Lean Month

  1. Good month: top up buffer, then fund goals and tax
  2. Lean month: draw the same wage, buffer fills the gap
  3. Long lean stretch: trim wants temporarily
  4. Always keep tax money separate and untouched

Business Structure Basics

Sole Trader

  1. Business profit is added to your personal income
  2. Taxed at your personal marginal rates
  3. You carry the debts personally
  4. Lowest cost and paperwork of the three

A Simple Decision Path

  1. 1. Note the risk level of your work
  2. 2. Estimate your likely profit and tax position
  3. 3. Decide if you need partners or investors
  4. 4. Start as a sole trader if simple, or incorporate if risk or scale warrants
  5. 5. Get accounting and legal advice before deciding

Agency Agreements in NZ: Before You Sign

&#9200; Your Cancellation Rights

  1. Change of mind: cancel in writing by 5pm on the first working day after you are given your copy
  2. Unsolicited approach: five working days to cancel, and it does not have to be in writing
  3. Longer than 90 days: either party may cancel any time after day 90, in writing

Workings are taken from the guides listed above and are worked examples for education, not advice. Figures used in an example were current when the guide was written; the guide holds the maintained figure. Last reviewed 2026-09-06. See also every question the site answers and the guides.