Frequencies for mod_year variable in vehnit dataset : MODEL YEAR | Freq. Percent Cum. ------------+----------------------------------- 1959 | 1 0.07 0.07 1960 | 1 0.07 0.14 1962 | 1 0.07 0.22 1966 | 1 0.07 0.29 1967 | 2 0.14 0.43 1968 | 1 0.07 0.50 1969 | 1 0.07 0.57 1970 | 1 0.07 0.65 1972 | 4 0.29 0.93 1973 | 1 0.07 1.01 1974 | 1 0.07 1.08 1975 | 1 0.07 1.15 1976 | 2 0.14 1.29 1977 | 3 0.22 1.51 1978 | 3 0.22 1.72 1979 | 4 0.29 2.01 1980 | 2 0.14 2.15 1981 | 8 0.57 2.73 1983 | 6 0.43 3.16 1984 | 3 0.22 3.37 1985 | 20 1.44 4.81 1986 | 14 1.01 5.81 1987 | 22 1.58 7.39 1988 | 19 1.36 8.76 1989 | 32 2.30 11.06 1990 | 36 2.58 13.64 1991 | 39 2.80 16.44 1992 | 38 2.73 19.17 1993 | 55 3.95 23.12 1994 | 65 4.67 27.78 1995 | 71 5.10 32.88 1996 | 65 4.67 37.54 1997 | 68 4.88 42.43 1998 | 62 4.45 46.88 1999 | 81 5.81 52.69 2000 | 101 7.25 59.94 2001 | 96 6.89 66.83 2002 | 79 5.67 72.51 2003 | 85 6.10 78.61 2004 | 80 5.74 84.35 2005 | 110 7.90 92.25 2006 | 71 5.10 97.34 2007 | 12 0.86 98.21 9999 | 25 1.79 100.00 ------------+----------------------------------- Total | 1,393 100.00 by Jean Roth , jroth@nber.org , 18 Apr 2016