Yield to Maturity (YTM) is the total return you can expect from a bond if you hold it until it matures. It accounts for the bond's current market price, coupon payments, face value, and time to maturity. YTM is expressed as an annual percentage rate.
| Term | Definition | Example |
|---|---|---|
| Face Value (Par) | Amount paid at maturity | $1,000 |
| Coupon Rate | Annual interest rate on face value | 5% ($50/year) |
| Market Price | Current trading price | $950 (below par) |
| Maturity Date | When principal is repaid | 5 years from now |
| YTM | Total annual return to maturity | 6.2% |
NZ Government Bond:
Interpretation: If you buy this bond for $950 and hold to maturity, you'll earn approximately 5.13% annually through coupon payments plus the gain from price appreciation to par value.
You own a bond paying 4% coupon. New bonds now pay 6%. Your bond becomes less attractive, so its price falls to compensate buyers with higher YTM.
| Scenario | Market Price | YTM | Term |
|---|---|---|---|
| Interest rates rise | $900 (discount) | 6.5% | Trading below par |
| Interest rates unchanged | $1,000 (par) | 4.0% | Trading at par |
| Interest rates fall | $1,050 (premium) | 2.8% | Trading above par |
| Measure | Formula | What It Shows |
|---|---|---|
| Current Yield | Annual Coupon / Market Price | Simple income return only |
| Coupon Rate | Annual Coupon / Face Value | Original fixed rate |
| YTM | Complex (includes capital gains) | Total return if held to maturity |
YTM is most comprehensive because it includes both income and capital appreciation.
Compare bonds with different coupons, prices, and maturities on equal footing.
Choose bonds that meet your required return threshold.
YTM reflects market expectations about future interest rates.
Government bond YTM is the risk-free rate used in CAPM and other models.
| Bond Type | Typical YTM | Risk Level |
|---|---|---|
| NZ Government 10-year | 4.0-4.5% | Very low |
| AAA Corporate | 4.5-5.5% | Low |
| BBB Corporate | 5.5-7.0% | Moderate |
| High Yield (Junk) | 8.0-12.0% | High |
| Emerging Market | 7.0-10.0% | High |
YTM assumes you:
1. Hold the bond to maturity (no selling early)
2. Reinvest all coupon payments at the same YTM rate
3. Issuer doesn't default
If any assumption fails, actual return may differ from YTM.
Duration measures how sensitive a bond's price is to interest rate changes.
| Maturity | Typical Duration | Price Sensitivity |
|---|---|---|
| 2 years | 1.9 years | Low |
| 5 years | 4.5 years | Moderate |
| 10 years | 8.2 years | High |
| 30 years | 18 years | Very high |
Ignores reinvestment risk: Assumes you can reinvest coupons at YTM rate (unlikely)
Assumes held to maturity: If you sell early, actual return may differ
Doesn't reflect default risk: High YTM may signal high default risk
Point-in-time measure: YTM changes daily with market prices
Exact YTM requires solving for the discount rate that equates present value of cash flows to current price:
This requires trial and error or a financial calculator. For approximation, use the simplified formula.
Contact Energy Bond:
Interpretation: Bond trades below face value because its 5.5% coupon is below current market rates. YTM of 6.92% compensates buyer through both coupons and capital appreciation.
Fletcher Building Bond:
Interpretation: Bond trades above face value because 7% coupon exceeds current market rates. YTM of 4.81% is lower than coupon because buyer pays premium and will receive capital loss at maturity.
NZ Treasury Bill (no coupons, just discount):
All return comes from buying at discount and receiving face value at maturity.
Which bond offers better return?
Same bond, different maturities:
| Years to Maturity | Price | YTM |
|---|---|---|
| 1 year | $980 | 7.14% |
| 5 years | $920 | 6.92% |
| 10 years | $880 | 6.84% |
| 20 years | $850 | 6.78% |
Longer maturity bonds trade at bigger discounts because buyers lock in rates for longer periods.
Plot YTM against maturity to see yield curve:
| Maturity | YTM | Spread vs 1-year |
|---|---|---|
| 1 year | 3.5% | - |
| 2 years | 3.8% | +0.3% |
| 5 years | 4.2% | +0.7% |
| 10 years | 4.5% | +1.0% |
Normal upward-sloping curve compensates investors for locking in money longer.
Retiree choosing between bonds for income
| Factor | 2-Year Bond | 10-Year Bond |
|---|---|---|
| YTM | 3.92% | 4.26% |
| Annual income | $350 | $450 |
| Price risk | Low (2-year duration) | High (8+ year duration) |
| Reinvestment risk | High (reinvest in 2 years) | Low (locked 10 years) |
Investor comparing safety vs return
| Investment | Annual Income | 5-Year Total | Risk |
|---|---|---|---|
| Government | $400 | $2,000 | None |
| Fonterra | $596 | $2,980 | Moderate |
| Extra return | $196 | $980 | - |
Decision factors: Is extra $980 over 5 years worth the corporate default risk? For conservative investors, government bond safer. For return-focused investors, Fonterra offers 50% more yield.
Investor holds bond when rates rise
Option 1: Sell Now
Option 2: Hold to Maturity
Rising interest rates cause bond prices to fall, creating paper losses. But if you hold to maturity, you still receive all promised coupons plus face value. Only realize loss if you sell. This is why bonds are considered "safe" for buy-and-hold investors despite price volatility.
Retiree creates steady income stream
| Bond | Maturity | Face Value | Price | Coupon | YTM |
|---|---|---|---|---|---|
| A | 1 year | $20,000 | $19,800 | 3.5% | 4.5% |
| B | 2 years | $20,000 | $19,600 | 4.0% | 5.0% |
| C | 3 years | $20,000 | $19,400 | 4.5% | 5.5% |
| D | 4 years | $20,000 | $19,200 | 5.0% | 6.0% |
| E | 5 years | $20,000 | $19,000 | 5.5% | 6.5% |
Complete this quiz on Yield to Maturity
If you've found a bug, or would like to contact us please click here.
Calculate.co.nz is partnered with Interest.co.nz for New Zealand's highest quality calculators and financial analysis.
© 2019โ2025 Calculate.co.nz. All rights reserved.
All content on this website, including calculators, tools, source code, and design, is protected under the Copyright Act 1994 (New Zealand). No part of this site may be reproduced, copied, distributed, stored, or used in any form without prior written permission from the owner.
All calculators and tools are provided for educational and indicative purposes only and do not constitute financial advice.
Calculate.co.nz is part of the
realtor.co.nz,
GST Calculator,
GST.co.nz, and
PAYE Calculator group.
Calculate.co.nz is also partnered with
Health Based Building and
Premium Homes to promote informed choices that lead to better long-term outcomes for Kiwi households.