The refinance share of mortgage activity decreased to 72.6 percent of total applications from 73.4 percent the previous week.
The government share of purchase applications remained steady at 37 percent, a slight increase from a couple of weeks ago when the share was 36.4 percent. During the past three weeks, the government share of purchase applications has hit the lowest level since 2009.
In March, the investor share of applications for home purchases was 5.7 percent, a slight decrease from 6.1 percent in February.
In addition, the share of purchase mortgages for second homes remained constant at 5.8 percent.
While the housing market makes slow yet gradual improvement, mortgage rates have remained at historic lows, making housing affordable although available credit remains restrained.
Last week, the average contract interest rate for 30-year fixed-rate mortgages with conforming loan balances ($417,500 or less) increased to 4.05 percent from 4.04.
The rate for 30-year fixed-rate mortgages with jumbo loan balances (greater than $417,500) increased to 4.32 percent from 4.27.
But the rate for 30-year fixed-rate mortgages backed by the Federal Housing Administration (FHA) fell to 3.8 percent from 3.81, the lowest rate in the history of the survey.
The rate for 15-year fixed-rate mortgages decreased to 3.31 percent from 3.32, also the lowest rate in the survey's history.