According to the Mortgage Bankers Association's Weekly Applications Survey, average mortgage rates fell across all loan categories last week, including 30-year fixed-rate loans with both conforming and jumbo balances, loans backed by the Federal Housing Administration, and 15-year fixed-rate mortgages. Despite lower rates, however, demand for loans also fell, dropping 3.3 percent compared to the week before. Most of the drop was due to declining refinance activity - compared with purchase demand, which only fell 1 percent. Lynn Fisher, MBA's vice president of research and economics, says declining refinance demand is to be expected. “There are fewer borrowers remaining who are able to benefit from low rates,” Fisher told CNBC. “The decline in average refinance loan size is also a feature of a declining refinance market. Borrowers with larger loan balances tend to be more rate sensitive. As refinance applications surge, average loan size tends to go up. As we return to a more normal level of refinance applications, the mix of borrowers returns to normal and average loan size declines.” Demand for loans to buy homes, on the other hand, is 25 percent higher than last year at the same time and expected to spike as the spring season gets underway. The MBA's weekly survey covers 75 percent of all retail residential mortgage applications and has been conducted since 1990.