Frequencies for first 10,000 rows of pct020b030 variable in sf12010860us37 dataset :

Maritime/me |
     rchant |
    vessels |
      (900) |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,981       99.81       99.81
          1 |          5        0.05       99.86
          2 |          3        0.03       99.89
          3 |          2        0.02       99.91
          4 |          2        0.02       99.93
          5 |          2        0.02       99.95
          6 |          1        0.01       99.96
         10 |          1        0.01       99.97
         13 |          1        0.01       99.98
         19 |          1        0.01       99.99
         20 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 17 Apr 2017