The Mortgage Bankers Association said its Market Composite Index moved lower last week, apparently indifferent to a slight improvement in mortgage interest rates. The Index, which measures loan application volume, decreased 0.7 percent on a seasonally adjusted basis from one week earlier.  On an unadjusted basis, the Index declined 0.4 percent compared with the previous week. The Refinance Index decreased 2.0 percent from the previous week and was 9.0 percent lower than the same week one year ago. The refinance share of mortgage activity accounted for 30.8 percent of total applications compared to 31.2 percent the previous week. [refiappschart] The Purchase Index ticked down 0.2 percent both before and after its seasonal adjustment.  It was 16.0 percent lower than the same week one year ago. [purchaseappschart] “Mortgage application activity was muted last week despite slightly lower mortgage rates. The 30-year fixed rate edged lower to 6.93