Frequencies for first 10,000 rows of su variable in nhamcsopd1997 dataset :

   hospital |
   sampling |
  unit code |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,264       12.64       12.64
          2 |        811        8.11       20.75
          3 |        708        7.08       27.83
          4 |        725        7.25       35.08
          5 |        565        5.65       40.73
          6 |        528        5.28       46.01
          7 |        525        5.25       51.26
          8 |        528        5.28       56.54
          9 |        402        4.02       60.56
         10 |        376        3.76       64.32
         11 |        246        2.46       66.78
         12 |        336        3.36       70.14
         13 |        201        2.01       72.15
         14 |        176        1.76       73.91
         15 |        175        1.75       75.66
         16 |        235        2.35       78.01
         17 |        203        2.03       80.04
         18 |        166        1.66       81.70
         19 |        114        1.14       82.84
         20 |         49        0.49       83.33
         21 |         95        0.95       84.28
         22 |         75        0.75       85.03
         23 |         54        0.54       85.57
         24 |        108        1.08       86.65
         25 |         96        0.96       87.61
         26 |         21        0.21       87.82
         27 |         15        0.15       87.97
         28 |         42        0.42       88.39
         29 |        100        1.00       89.39
         30 |         67        0.67       90.06
         31 |         61        0.61       90.67
         32 |         47        0.47       91.14
         33 |         49        0.49       91.63
         35 |         66        0.66       92.29
         36 |         52        0.52       92.81
         38 |         58        0.58       93.39
         40 |         34        0.34       93.73
         41 |         23        0.23       93.96
         42 |         38        0.38       94.34
         44 |         58        0.58       94.92
         47 |         26        0.26       95.18
         48 |         32        0.32       95.50
         49 |         29        0.29       95.79
         50 |         49        0.49       96.28
         54 |         21        0.21       96.49
         58 |         29        0.29       96.78
         59 |         54        0.54       97.32
         65 |         23        0.23       97.55
         66 |         62        0.62       98.17
         72 |         30        0.30       98.47
         75 |          7        0.07       98.54
         83 |         29        0.29       98.83
         90 |         28        0.28       99.11
        107 |         27        0.27       99.38
        108 |         32        0.32       99.70
        131 |         30        0.30      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016