Bonds are loan taken by companies with a definite maturity period. During the period, according to the terms of the contract, a fixed periodic payments in the form of interests are made and at the end of the period the maturity value is redeemed. Since, the volatility of bonds is lower than stocks, bonds are preferred over stocks. Also, tax advantage is received on the interest paid. However, they carry risks such as interest rate risk, prepayment risk, credit and liquidity risk.
Interest rate risk refers to the fluctuation of market interest rate. If the market rate increases, the lenders are at a loss, since they are receiving lower return on similar risk bonds. Also, the issuer of bonds carry credit risk, that is the risk of default. In such cases, the lender might not get the periodic payments, if the issuer goes bankrupt.
When the bonds are callable, then the investor might face reinvestment risk, in such cases, if the market interest starts declining, the bonds might be called back and the yield earned on the investment would decrease. The investors would then have to invest their money at a lower interest rate.
When the risk on bonds increases, the expected return also increases. This is because, the investors would want to be compensated more for the risk they are taking. This is the reason why lower rated bonds give higher yield as compared to higher rated bonds.
Preferred stocks have the characteristics of both debt and equity. They pay fixed dividends on the par value of the stock. Investors believe that preferred stock provide higher dividend yield and have the potential of capital appreciation as well.
Preferred stock like bonds are exposed to interest rate risk. The value of prefrred stocks decreases as the interest rate increases. In addition to this they have liquidity risk and the risk of being called, as some companies can call them back when the interest rate starts declining in the market.
Therefore, to compensate the investors expect higher return. The risk associated with preferred stocks is more than bonds and hence the expected rate of return on preferred stocks is usually more than bonds.
Common stocks are equity and they are the most riskiest type of financing of all the three. This is because, the owners of common stock will be the last to be compensated when the company gets liquidated or bankrupt. The investors do not have any guarantees in the form of periodic payment or capital appreciation. The return on such stock depends on the volatility or the systematic risk of the stock. Higher the volatility, higher is the expected rate of return.
The expected rate of return or in other words the cost to compensate the risk for common stock is the highest amongst the other form of financing.
Therefore, bonds usually have the lowest expected rate of return followed by preferred stock and then common stock.