Frequencies for mod_year variable in vehnit dataset : MODEL YEAR | Freq. Percent Cum. ------------+----------------------------------- 1961 | 1 0.08 0.08 1963 | 1 0.08 0.15 1964 | 2 0.15 0.30 1967 | 3 0.23 0.53 1970 | 3 0.23 0.75 1972 | 1 0.08 0.83 1973 | 2 0.15 0.98 1974 | 1 0.08 1.05 1975 | 1 0.08 1.13 1976 | 2 0.15 1.28 1978 | 4 0.30 1.58 1979 | 4 0.30 1.88 1980 | 6 0.45 2.33 1981 | 4 0.30 2.64 1983 | 3 0.23 2.86 1984 | 4 0.30 3.16 1985 | 9 0.68 3.84 1986 | 18 1.36 5.20 1987 | 10 0.75 5.95 1988 | 14 1.05 7.00 1989 | 22 1.66 8.66 1990 | 31 2.33 10.99 1991 | 41 3.09 14.08 1992 | 34 2.56 16.64 1993 | 43 3.24 19.88 1994 | 46 3.46 23.34 1995 | 56 4.22 27.56 1996 | 61 4.59 32.15 1997 | 81 6.10 38.25 1998 | 71 5.35 43.60 1999 | 78 5.87 49.47 2000 | 90 6.78 56.25 2001 | 80 6.02 62.27 2002 | 75 5.65 67.92 2003 | 69 5.20 73.12 2004 | 88 6.63 79.74 2005 | 74 5.57 85.32 2006 | 79 5.95 91.27 2007 | 91 6.85 98.12 2008 | 6 0.45 98.57 9999 | 19 1.43 100.00 ------------+----------------------------------- Total | 1,328 100.00 by Jean Roth , jroth@nber.org , 18 Apr 2016