Frequencies for first 10,000 rows of exp_dt_num variable in drug2006q4 dataset : Expiration | date of the | drug. | (YYYYMMDD) | Freq. Percent Cum. ------------+----------------------------------- 31aug2004 | 1 0.01 0.01 14may2005 | 1 0.01 0.02 01jan2006 | 1 0.01 0.03 09feb2006 | 2 0.02 0.05 31mar2006 | 1 0.01 0.06 01aug2006 | 1 0.01 0.07 30sep2006 | 1 0.01 0.08 01oct2006 | 2 0.02 0.10 11oct2006 | 1 0.01 0.11 19oct2006 | 1 0.01 0.12 01nov2006 | 1 0.01 0.13 01dec2006 | 1 0.01 0.14 01jan2007 | 2 0.02 0.16 22jan2007 | 1 0.01 0.17 26jan2007 | 1 0.01 0.18 10feb2007 | 1 0.01 0.19 28feb2007 | 1 0.01 0.20 16mar2007 | 1 0.01 0.21 01apr2007 | 4 0.04 0.25 01may2007 | 4 0.04 0.29 31may2007 | 1 0.01 0.30 01jun2007 | 3 0.03 0.33 30jun2007 | 1 0.01 0.34 01aug2007 | 3 0.03 0.37 31aug2007 | 1 0.01 0.38 01sep2007 | 8 0.08 0.46 07sep2007 | 1 0.01 0.47 18sep2007 | 1 0.01 0.48 20sep2007 | 1 0.01 0.49 27sep2007 | 1 0.01 0.50 30sep2007 | 2 0.02 0.52 01oct2007 | 3 0.03 0.55 01nov2007 | 6 0.06 0.61 30nov2007 | 2 0.02 0.63 01dec2007 | 3 0.03 0.66 06dec2007 | 1 0.01 0.67 29dec2007 | 1 0.01 0.68 30dec2007 | 1 0.01 0.69 01jan2008 | 4 0.04 0.73 01feb2008 | 1 0.01 0.74 01mar2008 | 6 0.06 0.80 01apr2008 | 4 0.04 0.84 30apr2008 | 1 0.01 0.85 01may2008 | 2 0.02 0.87 11may2008 | 1 0.01 0.88 31may2008 | 2 0.02 0.90 01jun2008 | 3 0.03 0.93 30jun2008 | 1 0.01 0.94 01aug2008 | 1 0.01 0.95 31aug2008 | 1 0.01 0.96 01nov2008 | 1 0.01 0.97 30nov2008 | 1 0.01 0.98 01feb2009 | 6 0.06 1.04 01mar2009 | 1 0.01 1.05 01apr2009 | 3 0.03 1.08 30apr2009 | 1 0.01 1.09 01may2009 | 5 0.05 1.14 31jan2010 | 1 0.01 1.15 01jul2010 | 1 0.01 1.16 . | 9,884 98.84 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 18 Dec 2015