Frequencies for pmodyear variable in parkwork dataset : Vehicle | Model Year | Freq. Percent Cum. ------------+----------------------------------- 1950 | 1 0.10 0.10 1962 | 1 0.10 0.20 1963 | 1 0.10 0.30 1967 | 1 0.10 0.40 1968 | 1 0.10 0.50 1969 | 2 0.20 0.70 1971 | 2 0.20 0.90 1972 | 1 0.10 1.00 1973 | 2 0.20 1.20 1974 | 1 0.10 1.30 1976 | 2 0.20 1.50 1977 | 1 0.10 1.60 1979 | 1 0.10 1.70 1980 | 2 0.20 1.90 1981 | 1 0.10 2.00 1982 | 1 0.10 2.10 1983 | 1 0.10 2.20 1984 | 4 0.40 2.59 1985 | 3 0.30 2.89 1986 | 2 0.20 3.09 1988 | 10 1.00 4.09 1989 | 11 1.10 5.19 1990 | 15 1.50 6.69 1991 | 11 1.10 7.78 1992 | 15 1.50 9.28 1993 | 27 2.69 11.98 1994 | 27 2.69 14.67 1995 | 33 3.29 17.96 1996 | 35 3.49 21.46 1997 | 40 3.99 25.45 1998 | 47 4.69 30.14 1999 | 48 4.79 34.93 2000 | 65 6.49 41.42 2001 | 66 6.59 48.00 2002 | 50 4.99 52.99 2003 | 49 4.89 57.88 2004 | 63 6.29 64.17 2005 | 51 5.09 69.26 2006 | 55 5.49 74.75 2007 | 61 6.09 80.84 2008 | 59 5.89 86.73 2009 | 28 2.79 89.52 2010 | 35 3.49 93.01 2011 | 35 3.49 96.51 2012 | 5 0.50 97.01 9998 | 2 0.20 97.21 9999 | 28 2.79 100.00 ------------+----------------------------------- Total | 1,002 100.00 by Jean Roth , jroth@nber.org , 18 Apr 2016