Frequencies for first 10,000 rows of pct020c025 variable in sf12010860us37 dataset :

   Military |
ships (602) |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,994       99.94       99.94
          1 |          1        0.01       99.95
          2 |          1        0.01       99.96
          4 |          1        0.01       99.97
         17 |          1        0.01       99.98
         21 |          1        0.01       99.99
        202 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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