Nontraditional mortgage forms continue to account for a growing share of the market through the midway point in 2006 – representing 37 percent of current originations – with much of the recent momentum coming from subprime mortgages combining a 40-year amortization with a traditional 30-year term. Interest-only mortgages remain the biggest component of the nontraditional sector, according to the Inside Mortgage Finance MBS Database, which tracked over $1.015 trillion of residential mortgage securities issued during… [One data table included]