A heavy volume of $82.87 billion of jumbo mortgages flowed into the non-agency MBS market during the first quarter of 2005, slightly off the record pace set in the fourth quarter of last year. A new Inside MBS & ABS analysis reveals that jumbo securitization slipped 2.2 percent from the end of 2004, but remained well ahead of the pace set back in the first quarter of last year. Jumbo mortgages accounted for 34.0 percent…