Southern States Among Highest Default Rates, New England & Midwest States Lowest. Southern states in the U.S. had some of the highest default rates, according to the Department of Education’s default data. Mississippi’s default rate of 14.94% was the second highest in the country, behind only Nevada’s 18.16%, which was an outlier. Delinquency Rate (%) U.S. Residential Mortgage Delinquency Rates Seasonalyl Adjused Data, 1998Q2 to 2011Q1 Source: Mortgage Bankers Association / Haver Analytics Recession Period Prime Fixed -Rate Mortgages Prime Adjustable -Rate Mortgages Subprime Fixed -Rate Mortgages Subprime Adjustable -Rate Mortgages The National Delinquency Survey (NDS) is one of the most recognized sources for residential mortgage delinquency and foreclosure rates. Based on a sample of almost 40 million first lien loans serviced by mortgage companies, commercial banks, thrifts, credit unions and others, NDS provides quarterly delinquency and foreclosure statistics at the national, regional and state levels.