Frequencies for first 10,000 rows of mod_year variable in vehicle dataset : MODEL YEAR | Freq. Percent Cum. ------------+----------------------------------- 1932 | 1 0.01 0.01 1952 | 1 0.01 0.02 1955 | 1 0.01 0.03 1956 | 1 0.01 0.04 1957 | 1 0.01 0.05 1960 | 1 0.01 0.06 1963 | 3 0.03 0.09 1965 | 3 0.03 0.12 1966 | 6 0.06 0.18 1967 | 1 0.01 0.19 1968 | 6 0.06 0.25 1969 | 3 0.03 0.28 1970 | 1 0.01 0.29 1972 | 10 0.10 0.39 1973 | 3 0.03 0.42 1974 | 9 0.09 0.51 1975 | 3 0.03 0.54 1976 | 4 0.04 0.58 1977 | 11 0.11 0.69 1978 | 10 0.10 0.79 1979 | 9 0.09 0.88 1980 | 11 0.11 0.99 1981 | 15 0.15 1.14 1982 | 15 0.15 1.29 1983 | 21 0.21 1.50 1984 | 34 0.34 1.84 1985 | 40 0.40 2.24 1986 | 59 0.59 2.83 1987 | 63 0.63 3.46 1988 | 82 0.82 4.28 1989 | 104 1.04 5.32 1990 | 156 1.56 6.88 1991 | 163 1.63 8.51 1992 | 167 1.67 10.18 1993 | 249 2.49 12.67 1994 | 268 2.68 15.35 1995 | 376 3.76 19.11 1996 | 306 3.06 22.17 1997 | 426 4.26 26.43 1998 | 449 4.49 30.92 1999 | 543 5.43 36.35 2000 | 661 6.61 42.96 2001 | 664 6.64 49.60 2002 | 615 6.15 55.75 2003 | 637 6.37 62.12 2004 | 646 6.46 68.58 2005 | 670 6.70 75.28 2006 | 681 6.81 82.09 2007 | 685 6.85 88.94 2008 | 538 5.38 94.32 2009 | 283 2.83 97.15 2010 | 34 0.34 97.49 9999 | 251 2.51 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 18 Apr 2016