This calculator helps you build a bond or term deposit ladder in New Zealand, splitting a lump sum across several investments that mature in different years to balance access against return. A ladder solves the dilemma of fixed-income investing: lock everything into one long term and you get a good rate but no access, while keeping it all short means easy access but a lower rate and the risk of reinvesting the whole lot just when rates dip. By dividing your money into equal rungs maturing in years one, two, three and so on, you get some cash back every year to spend or reinvest, the longer rungs earn higher rates, and you smooth out interest rate movements because you are never reinvesting everything at a single point in time. You enter the total you want to invest, the number of rungs or years in the ladder, and the average interest rate, and the calculator shows the amount to place in each rung, the annual interest income while the ladder is fully invested, and the staggered maturity schedule. This is an especially popular approach for retirees drawing an income, who appreciate having a known sum maturing each year. It works equally well with bank term deposits or with bonds.
Equal rungs maturing one per year. Income assumes the ladder is fully invested at the average rate. Rates differ by term. Estimate only, not financial advice.
The calculator divides your total by the number of rungs to give the amount in each, with one rung maturing each year out to the length of the ladder. The annual interest income, while everything is invested, is the total times the average rate. In practice longer rungs earn a higher rate than shorter ones.
Investing 100,000 dollars across a 5 rung ladder puts 20,000 dollars into each of the 1 to 5 year terms. At an average 5 percent, the ladder earns about 5,000 dollars a year while fully invested, with 20,000 dollars maturing each year for access or reinvestment.
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