Mortgage application activity was mixed in two weekly surveys. The Mortgage Bankers Association (MBA) survey of gross application volume increased 13.6% on a seasonally adjusted basis for the week ending April 16 compared to one week ago. The Mortgage Maxx survey, adjusted to reflect the number of households that applied for a mortgage, declined 0.5% during the same period. “Treasury rates fell last week causing a decline in mortgage rates. As a result, refinance applications picked up over the week, as some borrowers took advantage of this recent rate volatility to lock in a low fixed-rate loan,” said MBA vice president of research and economics Michael Fratantoni. The MBA said its Refinance Index increased 15.8% from last week and the seasonally adjusted purchase index increased 10.1%. “Purchase applications continued to increase coming out of the Easter holiday, as we approach the end of the homebuyer tax credit, and are up modestly over last month,” Fratantoni said. Refinance applications took a 60% share of activity, up from 58.9% last week. The adjustable-rate mortgage (ARM) share of activity decreased to 6% from 6.3% last week. Write to Austin Kilgore.