Frequencies for contractid variable in pdp2017 dataset :

Contract ID |      Freq.     Percent        Cum.
------------+-----------------------------------
            |          1        0.10        0.10
      S0522 |         98        9.51        9.61
      S1030 |          4        0.39       10.00
      S2468 |          2        0.19       10.19
      S2668 |          4        0.39       10.58
      S2874 |          2        0.19       10.78
      S2893 |          8        0.78       11.55
      S4054 |          1        0.10       11.65
      S4607 |         33        3.20       14.85
      S4802 |        102        9.90       24.76
      S5540 |          2        0.19       24.95
      S5552 |          3        0.29       25.24
      S5584 |          2        0.19       25.44
      S5593 |          4        0.39       25.83
      S5596 |         36        3.50       29.32
      S5601 |        101        9.81       39.13
      S5609 |          4        0.39       39.51
      S5660 |        102        9.90       49.42
      S5715 |         12        1.17       50.58
      S5726 |          3        0.29       50.87
      S5743 |         14        1.36       52.23
      S5753 |          2        0.19       52.43
      S5768 |        102        9.90       62.33
      S5795 |          2        0.19       62.52
      S5805 |          1        0.10       62.62
      S5810 |         51        4.95       67.57
      S5820 |         55        5.34       72.91
      S5877 |          4        0.39       73.30
      S5884 |        150       14.56       87.86
      S5904 |          2        0.19       88.06
      S5916 |          4        0.39       88.45
      S5921 |         53        5.15       93.59
      S5953 |          2        0.19       93.79
      S5983 |          2        0.19       93.98
      S5993 |          2        0.19       94.17
      S6506 |          2        0.19       94.37
      S6986 |          1        0.10       94.47
      S7694 |         53        5.15       99.61
      S8067 |          4        0.39      100.00
------------+-----------------------------------
      Total |      1,030      100.00

by Jean Roth , jroth@nber.org , 6 Dec 2016