Frequencies for first 10,000 rows of pct020h025 variable in sf12010860us38 dataset :

   Military |
ships (602) |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,989       99.89       99.89
          4 |          2        0.02       99.91
          5 |          1        0.01       99.92
         12 |          1        0.01       99.93
         16 |          1        0.01       99.94
         18 |          1        0.01       99.95
         37 |          1        0.01       99.96
         49 |          1        0.01       99.97
        111 |          1        0.01       99.98
        175 |          1        0.01       99.99
       2584 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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