Frequencies for first 10,000 rows of prov4180 variable in posclia2010 dataset :

  number of |
  lab sites |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,617       96.17       96.17
          2 |        168        1.68       97.85
          3 |         71        0.71       98.56
          4 |         30        0.30       98.86
          5 |         21        0.21       99.07
          6 |         10        0.10       99.17
          7 |         12        0.12       99.29
          8 |          7        0.07       99.36
          9 |          5        0.05       99.41
         10 |          7        0.07       99.48
         11 |          3        0.03       99.51
         12 |          6        0.06       99.57
         13 |          6        0.06       99.63
         14 |          2        0.02       99.65
         15 |          6        0.06       99.71
         16 |          2        0.02       99.73
         17 |          3        0.03       99.76
         18 |          3        0.03       99.79
         19 |          4        0.04       99.83
         20 |          1        0.01       99.84
         21 |          1        0.01       99.85
         22 |          3        0.03       99.88
         24 |          2        0.02       99.90
         27 |          2        0.02       99.92
         32 |          2        0.02       99.94
         43 |          1        0.01       99.95
         65 |          1        0.01       99.96
         70 |          1        0.01       99.97
         77 |          1        0.01       99.98
        138 |          1        0.01       99.99
        315 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 26 Jan 2016