Frequencies for first 10,000 rows of effective_date variable in nadac20170823 dataset : Effective | Date of the | NADAC Per | Unit Cost | Freq. Percent Cum. ------------+----------------------------------- 21sep2016 | 22 0.22 0.22 23sep2016 | 1 0.01 0.23 01oct2016 | 1 0.01 0.24 12oct2016 | 1 0.01 0.25 13oct2016 | 3 0.03 0.28 19oct2016 | 71 0.71 0.99 23nov2016 | 28 0.28 1.27 01dec2016 | 2 0.02 1.29 14dec2016 | 4 0.04 1.33 21dec2016 | 66 0.66 1.99 26dec2016 | 13 0.13 2.12 31dec2016 | 7 0.07 2.19 01jan2017 | 142 1.42 3.61 02jan2017 | 2 0.02 3.63 04jan2017 | 38 0.38 4.01 06jan2017 | 18 0.18 4.19 09jan2017 | 2 0.02 4.21 16jan2017 | 1 0.01 4.22 18jan2017 | 71 0.71 4.93 19jan2017 | 1 0.01 4.94 23jan2017 | 2 0.02 4.96 17feb2017 | 1 0.01 4.97 22feb2017 | 305 3.05 8.02 23feb2017 | 2 0.02 8.04 02mar2017 | 1 0.01 8.05 08mar2017 | 3 0.03 8.08 15mar2017 | 1 0.01 8.09 17mar2017 | 1 0.01 8.10 22mar2017 | 136 1.36 9.46 23mar2017 | 3 0.03 9.49 29mar2017 | 2 0.02 9.51 01apr2017 | 3 0.03 9.54 03apr2017 | 4 0.04 9.58 07apr2017 | 4 0.04 9.62 12apr2017 | 2 0.02 9.64 19apr2017 | 106 1.06 10.70 24apr2017 | 10 0.10 10.80 02may2017 | 5 0.05 10.85 03may2017 | 1 0.01 10.86 16may2017 | 1 0.01 10.87 17may2017 | 138 1.38 12.25 31may2017 | 3 0.03 12.28 01jun2017 | 147 1.47 13.75 07jun2017 | 2 0.02 13.77 08jun2017 | 17 0.17 13.94 21jun2017 | 164 1.64 15.58 28jun2017 | 1 0.01 15.59 01jul2017 | 5 0.05 15.64 05jul2017 | 7 0.07 15.71 11jul2017 | 45 0.45 16.16 12jul2017 | 7 0.07 16.23 14jul2017 | 1 0.01 16.24 19jul2017 | 439 4.39 20.63 20jul2017 | 2 0.02 20.65 26jul2017 | 1 0.01 20.66 27jul2017 | 1 0.01 20.67 01aug2017 | 1 0.01 20.68 02aug2017 | 4 0.04 20.72 09aug2017 | 11 0.11 20.83 16aug2017 | 17 0.17 21.00 23aug2017 | 7,900 79.00 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 10 Feb 2018