Average and Effective Interest Rates
   
  
         The table below provides two types of interest rates—the
      average annual special-issue rate and the effective rate.
      
      -  The average special-issue
       interest rate for a calendar year is the average of the 
       12 monthly interest rates on new
       issues during the year. 
-  An effective interest rate for a calendar year is the interest earned in
       that year divided by the average level of assets held during the year.  This rate reflects
       the entire portfolio of securites held by the Social Security trust funds
       (OASI and DI).
       Effective rates for the trust funds on a combined basis are shown below; rates for
       each trust fund, separately, are also available.
       
 
 
       
       Average annual special-issue interest rates on new issues and effective
         annual interest rates (percent)
  
    | 
    
      | Year | Average | Effective |  
      | 1940 | 2.5 | 2.4 |  
      | 1941 | 2.5 | 2.4 |  
      | 1942 | 2.2 | 2.3 |  
      | 1943 | 1.9 | 2.1 |  
      | 1944 | 1.9 | 2.0 |  
      | 1945 | 1.9 | 2.1 |  
      | 1946 | 1.9 | 2.0 |  
      | 1947 | 2.0 | 1.9 |  
      | 1948 | 2.1 | 2.8 |  
      | 1949 | 2.1 | 1.3 |  
      | 1950 | 2.1 | 2.0 |  
      | 1951 | 2.2 | 2.9 |  
      | 1952 | 2.3 | 2.2 |  
      | 1953 | 2.4 | 2.3 |  
      | 1954 | 2.3 | 2.3 |  
      | 1955 | 2.3 | 2.2 |  
      | 1956 | 2.5 | 2.4 |  
      | 1957 | 2.5 | 2.5 |  
      | 1958 | 2.6 | 2.5 |  
      | 1959 | 2.6 | 2.6 |  
      | 1960 | 2.9 | 2.6 |  
      | 1961 | 3.8 | 2.8 |  
      | 1962 | 3.9 | 2.8 |  
      | 1963 | 3.9 | 2.9 |  
      | 1964 | 4.1 | 3.1 |  
      | 1965 | 4.2 | 3.2 |  
      | 1966 | 4.9 | 3.5 |  
      | 1967 | 5.0 | 3.8 |  
      | 1968 | 5.5 | 4.0 |  
      | 1969 | 6.6 | 4.4 |  | 
    
      | Year | Average | Effective |  
      | 1970 | 7.3 | 5.1 |  
      | 1971 | 6.0 | 5.3 |  
      | 1972 | 5.9 | 5.4 |  
      | 1973 | 6.6 | 5.8 |  
      | 1974 | 7.5 | 6.2 |  
      | 1975 | 7.4 | 6.6 |  
      | 1976 | 7.1 | 6.7 |  
      | 1977 | 7.1 | 7.0 |  
      | 1978 | 8.2 | 7.2 |  
      | 1979 | 9.1 | 7.5 |  
      | 1980 | 11.0 | 8.6 |  
      | 1981 | 13.3 | 9.9 |  
      | 1982 | 12.8 | 11.2 |  
      | 1983 | 11.0 | 10.8 |  
      | 1984 | 12.4 | 11.6 |  
      | 1985 | 10.8 | 11.2 |  
      | 1986 | 8.0 | 11.1 |  
      | 1987 | 8.4 | 10.1 |  
      | 1988 | 8.8 | 9.8 |  
      | 1989 | 8.7 | 9.6 |  
      | 1990 | 8.6 | 9.3 |  
      | 1991 | 8.0 | 9.1 |  
      | 1992 | 7.1 | 8.7 |  
      | 1993 | 6.1 | 8.3 |  
      | 1994 | 7.1 | 8.0 |  
      | 1995 | 6.9 | 7.8 |  
      | 1996 | 6.6 | 7.6 |  
      | 1997 | 6.6 | 7.5 |  
      | 1998 | 5.6 | 7.2 |  
      | 1999 | 5.9 | 6.9 |  | 
    
      | Year | Average | Effective |  
      | 2000 | 6.2 | 6.9 |  
      | 2001 | 5.2 | 6.6 |  
      | 2002 | 4.9 | 6.4 |  
      | 2003 | 4.1 | 6.0 |  
      | 2004 | 4.3 | 5.7 |  
      | 2005 | 4.3 | 5.5 |  
      | 2006 | 4.8 | 5.3 |  
      | 2007 | 4.7 | 5.3 |  
      | 2008 | 3.6 | 5.1 |  
      | 2009 | 2.9 | 4.9 |  
      | 2010 | 2.8 | 4.6 |  
      | 2011 | 2.4 | 4.4 |  
      | 2012 | 1.5 | 4.1 |  
      | 2013 | 1.9 | 3.8 |  
      | 2014 | 2.3 | 3.6 |  
      | 2015 | 2.0 | 3.4 |  
      | 2016 | 1.8 | 3.2 |  
      | 2017 | 2.3 | 3.0 |  
      | 2018 | 2.9 | 2.9 |  
      | 2019 | 2.2 | 2.8 |  
      | 2020 | 1.0 | 2.6 |  
      | 2021 | 1.4 | 2.5 |  
      | 2022 | 3.0 | 2.4 |  
      | 2023 | 4.1 | 2.4 |  
      | 2024 | 4.3 | 2.5 |  |