Running yield is commonly referred to as YTM (yield to maturity) for bonds. It is a measurement of the total investment earnings expected over the life of the bond. The term "running" refers to a continuous investment; that is, the expectation is to hold the bond to maturity. Investors use the running yield to compare the lifetime income yield on similar debt products.
Determine the par value of the bond. Par (face) value is the stated value of the bond. This is the amount the investor will be paid when the bond reaches maturity. The most common par value amounts are $100 and $1,000. You can determine the par value by looking at the prospectus (financial disclosure document) for the bond issuance you own which is a required document for all bond issues. If you do not have it, contact the company or institution which sold you the bond to request one. The par value will be on the first page. Let's say the par value is $1,000.
Calculate the purchase price of the bond. This is the initial price you paid for the bond. It is common for investors to pay less than par for a bond. Let's say the amount you paid for the bond is $800.
Determine the coupon rate. This is the stated rate of interest the bond pays. This amount is usually included in the title of the bond issuance, i.e., "General Electric 30yr Bonds 10," where 10 is the coupon rate. It can also be found on the first page of the prospectus. Let's say the coupon rate is 8 percent.
Divide the par value by the purchase price of the bond. The calculation is $1,000 / $800 or .8.
Calculate the running yield. Multiply the figure in Step 4 by the coupon rate. The calculation is .8 x .08 = 0.064 or 6.4 percent.