The non-agency MBS market surged to $1.70 trillion in outstanding securities in the first quarter of 2006, according to a new analysis by Inside MBS & ABS. Non-agency MBS, including jumbo, subprime, Alt A and securities backed by second mortgages, accounted for 31.5 percent of all mortgage-backed securities in the market as of the end of the first quarter. The sector has more than tripled in size since the first quarter of 2003, when the… [One data table included]