Frequencies for first 10,000 rows of tbo variable in natl2003 dataset :

Total Birth |
  Order U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      2,768       27.68       27.68
          2 |      2,537       25.37       53.05
          3 |      1,633       16.33       69.38
          4 |      1,059       10.59       79.97
          5 |        532        5.32       85.29
          6 |        327        3.27       88.56
          7 |        180        1.80       90.36
          8 |        106        1.06       91.42
          9 |         89        0.89       92.31
         10 |         46        0.46       92.77
         11 |         30        0.30       93.07
         12 |         15        0.15       93.22
         13 |          8        0.08       93.30
         14 |          9        0.09       93.39
         15 |          2        0.02       93.41
         16 |          5        0.05       93.46
         18 |          1        0.01       93.47
         19 |          1        0.01       93.48
         99 |        652        6.52      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015