Mortgage interest rates have a very significant impact on the overall long-term cost of purchasing a home through financing. On the one hand, mortgage borrowers are seeking the lowest possible rates, but on the other hand, mortgage lenders have to manage their risk through the interest rates they charge. The lowest mortgage interest rates are only available to borrowers with the most solid finances and sterling credit histories.
While the financial health of borrowers affects the specific interest rates they can obtain, the general level of mortgage interest rates is influenced by a number of critical economic factors, as well as government financial policy. The factors that influence mortgage rates all represent basic rules of supply and demand in one form or another.
The gradual upward movement of prices due to inflation is an important factor in the overall economy and a critical factor for mortgage lenders. Inflation erodes the purchasing power of dollars over time. Mortgage lenders generally have to maintain interest rates at a level that is at least sufficient to overcome the erosion of purchasing power through inflation to ensure that their interest returns represent a real net profit. For example, if mortgage rates are at 5%, but the level of annual inflation is at 2%, then the lender's real return on a loan in terms of the purchasing power of the dollars they received in repayment is only 3%. Therefore, mortgage lenders carefully monitor the rate of inflation and adjust rates accordingly.
Mortgage rates are also influenced by economic growth indicators such as gross domestic product (GDP) and the employment rate. Higher economic growth levels generally produce higher incomes and higher levels of consumer spending, including more consumers looking to obtain mortgage loans for home purchases. The upswing in overall demand for mortgages tends to propel mortgage rates higher, since there is only a certain supply of money that lenders have available to lend out. Naturally, the opposite effect results from a weakening economy. Employment and wages decline, leading to decreased demand for home loans, which in turn puts downward pressure on the interest rates offered by mortgage lenders.
The monetary policy pursued by the Federal Reserve Bank is one of the most important factors influencing both the economy generally and interest rates specifically, including mortgage rates. The Federal Reserve does not set the specific interest rates in the mortgage market, but its actions in establishing the Fed Funds rate and adjusting the money supply upward or downward have a significant impact on the interest rates available to the borrowing public. Generally, increases in the money supply put downward pressure on rates, while tightening the money supply pressures rates upward.
Banks and other investment firms market mortgage-backed securities (MBSs) as investment products. The yields available from these debt securities must be sufficiently high to attract buyers. Part of this equation is the fact that government and corporate bonds offer competing long-term fixed income investments. The yields available on these competing investment products affect the yields that are offered on MBSs. The overall condition of the larger bond market therefore indirectly affects the mortgage rates that lenders charge, since the lenders must generate sufficient yields for MBSs to make them competitive in the total debt security market.
One frequently used government bond benchmark that mortgage lenders often peg their interest rates to is the 10-Year Treasury bond yield. Typically, the average spread for MBSs above the 10-year Treasury bond yield is approximately 1.7%. MBS sellers must offer higher yields because repayment is not 100% guaranteed as it is with government bonds.
Trends and conditions in the housing market also affect mortgage rates. When fewer homes are being built or offered for resale, the decline in homes being purchased leads to a decline in the demand for mortgages and pressures interest rates downward. A recent trend that has also applied downward pressure to rates is an increasing number of consumers opting to rent rather than buy a home. Such changes in the availability of homes and consumer demand affect the levels at which mortgage lenders set loan rates.