Frequencies for first 10,000 rows of hour variable in person dataset :

       hour |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        343        3.43        3.43
          1 |        380        3.80        7.23
          2 |        292        2.92       10.15
          3 |        270        2.70       12.85
          4 |        226        2.26       15.11
          5 |        286        2.86       17.97
          6 |        255        2.55       20.52
          7 |        292        2.92       23.44
          8 |        239        2.39       25.83
          9 |        314        3.14       28.97
         10 |        315        3.15       32.12
         11 |        416        4.16       36.28
         12 |        520        5.20       41.48
         13 |        403        4.03       45.51
         14 |        503        5.03       50.54
         15 |        616        6.16       56.70
         16 |        643        6.43       63.13
         17 |        639        6.39       69.52
         18 |        616        6.16       75.68
         19 |        536        5.36       81.04
         20 |        560        5.60       86.64
         21 |        458        4.58       91.22
         22 |        416        4.16       95.38
         23 |        356        3.56       98.94
         24 |          6        0.06       99.00
         99 |        100        1.00      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 18 Apr 2016