Frequencies for first 10,000 rows of mod_year variable in vehicle dataset : MODEL YEAR | Freq. Percent Cum. ------------+----------------------------------- 1923 | 1 0.01 0.01 1932 | 1 0.01 0.02 1938 | 1 0.01 0.03 1950 | 1 0.01 0.04 1953 | 2 0.02 0.06 1954 | 1 0.01 0.07 1956 | 3 0.03 0.10 1957 | 1 0.01 0.11 1960 | 3 0.03 0.14 1961 | 2 0.02 0.16 1962 | 5 0.05 0.21 1963 | 5 0.05 0.26 1964 | 3 0.03 0.29 1965 | 10 0.10 0.39 1966 | 8 0.08 0.47 1967 | 8 0.08 0.55 1968 | 9 0.09 0.64 1969 | 11 0.11 0.75 1970 | 15 0.15 0.90 1971 | 17 0.17 1.07 1972 | 21 0.21 1.28 1973 | 32 0.32 1.60 1974 | 18 0.18 1.78 1975 | 18 0.18 1.96 1976 | 31 0.31 2.27 1977 | 28 0.28 2.55 1978 | 52 0.52 3.07 1979 | 52 0.52 3.59 1980 | 54 0.54 4.13 1981 | 57 0.57 4.70 1982 | 68 0.68 5.38 1983 | 77 0.77 6.15 1984 | 143 1.43 7.58 1985 | 194 1.94 9.52 1986 | 230 2.30 11.82 1987 | 277 2.77 14.59 1988 | 319 3.19 17.78 1989 | 354 3.54 21.32 1990 | 383 3.83 25.15 1991 | 435 4.35 29.50 1992 | 427 4.27 33.77 1993 | 492 4.92 38.69 1994 | 522 5.22 43.91 1995 | 648 6.48 50.39 1996 | 554 5.54 55.93 1997 | 594 5.94 61.87 1998 | 629 6.29 68.16 1999 | 725 7.25 75.41 2000 | 767 7.67 83.08 2001 | 769 7.69 90.77 2002 | 617 6.17 96.94 2003 | 55 0.55 97.49 9999 | 251 2.51 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 18 Apr 2016