FICO Scores Mixed in First Quarter, S&P Reports Credit scores on securitized fixed-rate subprime mortgages rose significantly in the first quarter, a new analysis by rating agency Standard & Poor’s reveals. The credit story wasn’t quite as good for adjustable-rate and mixed-collateral pools, however. In an update on deals it rated, S&P reported that the FICO scores on fixed-rate pools averaged 629 at the end of March, a rise of 9 points from the fourth-quarter