Date Debt Percent
Dec 31, 2011 67.70%
Dec 31, 2010 62.80%
Dec 31, 2009 54.10%
Dec 31, 2008 40.50%
Dec 31, 2007 36.30%
Dec 31, 2006 36.60%
Dec 31, 2005 36.90%
Dec 31, 2004 36.80%
Dec 31, 2003 35.60%
Dec 31, 2002 33.60%
Dec 31, 2001 32.50%
Dec 31, 2000 34.70%
Dec 31, 1999 39.40%
Dec 31, 1998 43.00%
Dec 31, 1997 45.90%
Dec 31, 1996 48.40%
Dec 31, 1995 49.10%
Dec 31, 1994 49.20%
Dec 31, 1993 49.30%
Dec 31, 1992 48.10%
Dec 31, 1991 45.30%
Dec 31, 1990 42.10%
Dec 31, 1989 40.60%
Dec 31, 1988 41.00%
Dec 31, 1987 40.60%
Dec 31, 1986 39.50%
Dec 31, 1985 36.40%
Dec 31, 1984 34.00%
Dec 31, 1983 33.10%
Dec 31, 1982 28.70%
Dec 31, 1981 25.80%
Dec 31, 1980 26.10%
Dec 31, 1979 25.60%
Dec 31, 1978 27.40%
Dec 31, 1977 27.80%
Dec 31, 1976 27.50%
Dec 31, 1975 25.30%
Dec 31, 1974 23.90%
Dec 31, 1973 26.00%
Dec 31, 1972 27.40%
Dec 31, 1971 28.10%
Dec 31, 1970 28.00%
Dec 31, 1969 29.30%
Dec 31, 1968 33.30%
Dec 31, 1967 32.90%
Dec 31, 1966 34.90%
Dec 31, 1965 37.90%
Dec 31, 1964 40.00%
Dec 31, 1963 42.40%
Dec 31, 1962 43.70%
Dec 31, 1961 45.00%
Dec 31, 1960 45.60%
Dec 31, 1959 47.90%
Dec 31, 1958 49.20%
Dec 31, 1957 48.60%
Dec 31, 1956 52.00%
Dec 31, 1955 57.20%
Dec 31, 1954 59.50%
Dec 31, 1953 58.60%
Dec 31, 1952 61.60%
Dec 31, 1951 66.90%
Dec 31, 1950 80.20%
Dec 31, 1949 79.00%
Dec 31, 1948 84.30%
Dec 31, 1947 96.20%
Dec 31, 1946 108.70%
Dec 31, 1945 106.20%
Dec 31, 1944 88.30%
Dec 31, 1943 70.90%
Dec 31, 1942 47.00%
Dec 31, 1941 42.30%
Dec 31, 1940 44.20%