Frequencies for first 10,000 rows of esrd_ntwrk_num variable in pos2009 dataset :

       ESRD |
  NETWORK # |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,145       91.45       91.45
         05 |          1        0.01       91.46
         08 |        134        1.34       92.80
         13 |         95        0.95       93.75
         15 |        146        1.46       95.21
         16 |          9        0.09       95.30
         17 |        167        1.67       96.97
         18 |        303        3.03      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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