Its been a longstanding and usually treacherous tradition in the mortgage industry that when origination volume starts to sag, lenders begin to expand the credit box. One quarter does not a trend make, but the pattern in credit characteristics of loans sold to Fannie Mae and Freddie Mac suggest that some easing may be underway as the market works to sustain production volume. A new Inside Mortgage Trends analysis of first-quarter sales to the government-sponsored enterprises ... [Includes one data chart]