Nonprime mortgages are performing better than expected and prepayment rates remain elevated, according to industry analysts. Fitch Ratings noted that 60+ day delinquency rates on nonprime mortgages in post-crisis mortgage-backed securities rated by the firm were less than 4.00 percent as of August. “The performance of Fitch-rated nonprime transactions has outperformed initial projections,” the rating service said. The average conditional prepayment rate ... [Includes one data chart]