Frequencies for pv_config variable in parkwork dataset :

    Vehicle |
Configurati |
         on |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        828       82.63       82.63
          1 |         43        4.29       86.93
          2 |         30        2.99       89.92
          4 |          7        0.70       90.62
          5 |          3        0.30       90.92
          6 |         73        7.29       98.20
          7 |          2        0.20       98.40
         19 |          2        0.20       98.60
         20 |          1        0.10       98.70
         21 |          7        0.70       99.40
         98 |          5        0.50       99.90
         99 |          1        0.10      100.00
------------+-----------------------------------
      Total |      1,002      100.00

by Jean Roth , jroth@nber.org , 18 Apr 2016