Frequencies for first 10,000 rows of serumres variable in namcs2014 dataset :

 Most recent result for |
       serum creatinine |
                (mg/dL) |      Freq.     Percent        Cum.
------------------------+-----------------------------------
                  Blank |      5,280       52.80       52.80
                Unknown |          2        0.02       52.82
N/A, provider not asked |      2,703       27.03       79.85
                      0 |      1,176       11.76       91.61
                      1 |        759        7.59       99.20
                      2 |         49        0.49       99.69
                      3 |         11        0.11       99.80
                      4 |          3        0.03       99.83
                      5 |          4        0.04       99.87
                      6 |          2        0.02       99.89
                      7 |          1        0.01       99.90
                      8 |          1        0.01       99.91
                     10 |          1        0.01       99.92
                     11 |          1        0.01       99.93
                     15 |          1        0.01       99.94
                     18 |          1        0.01       99.95
                     21 |          1        0.01       99.96
                     24 |          1        0.01       99.97
                     49 |          1        0.01       99.98
                     79 |          1        0.01       99.99
                     81 |          1        0.01      100.00
------------------------+-----------------------------------
                  Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 27 Mar 2017