Bond Yield Calculation: Understanding Annual Return & Real Returns

A bond's annual rate of return represents the profit you've earned on it during the year. It's expressed in a percentage format. If you know your bond's coupon rate, its value during the year and the annual inflation rate, you can calculate both the nominal rate of return and the real rate of return you earned on a bond.

Annual Nominal Rate of Return

The nominal rate of return represents the actual rate of profit you earned on a bond during the year. Calculating it involves three steps.

1. Determine how much interest you earned on the bond during the year by multiplying its face value by its coupon rate. For example, if you have a $1,000 bond with a coupon rate of 4 percent, you'd earn $40 in interest each year.
   
2. Calculate how much the value of the bond appreciated during the year. Look at how much the bond was selling for on January 1, the beginning of the year, on a bond market. Check its price again on December 31 of the same year. For example, if the bond was selling for $1,000 on January 1 and $1,030 on December 31, the annual appreciation for the calendar year is $30.
3. Add the interest earned to the price appreciation and divide it by the bond's price at the beginning of the year. In our example, that would be $40 in interest plus $30 in appreciation -- or $70 -- divided by the beginning price of the bond -- $1,000 -- for a 7 percent annual rate of return.

Annual Real Rate of Return

You can also calculate the real rate of return on a bond. The real rate of return represents the rate of profit you earned adjusted for the effects of inflation -- in other words, the rate of profit you would have earned if no inflation had occurred during the year.

1. Determine your nominal rate of return and add one to the percentage. In our example, that would be one plus 7 percent, or 1.07.
   
2. Determine the inflation rate for the year. You can find this data from a source like USInflationCalculator.com, which pulls data from the Bureau of Labor Statistics. For example, if you're calculating the real rate of return for the calendar year 2014, the ending inflation rate for the year -- noted in the December column -- is 0.8 percent.
3. Add one to the inflation rate. In our example, that would be 1.008.
4. Divide your total from step 1 by your total from step 3 and subtract one. In our example, that would be 1.07 divided by 1.008 -- or 1.062 --- minus one for a total of 0.062. Your real annual rate of return on your bond, adjusted for the 0.8 percent inflation that occurred during the year, is 6.2 percent.