New primary mortgage insurance activity declined in step with slowing mortgage origination activity in the first quarter of 2011, and private MIs took more than their share of the hit, according to a new ranking and analysis by Inside Mortgage Finance. A total of $93.54 billion of mortgages originated in the first three months of the year carried primary MI coverage, down 20.3 percent from the fourth quarter of 2010. That was, however, less severe than the 35.0 percent drop in new loan originations over the same period. As refinance transactions represented a smaller share of... [Includes two data charts]