Frequencies for first 10,000 rows of exp_dt_num variable in drug2009q1 dataset : Expiration | date of the | drug. | (YYYYMMDD) | Freq. Percent Cum. ------------+----------------------------------- 01jan2008 | 1 0.01 0.01 01may2008 | 1 0.01 0.02 11sep2008 | 1 0.01 0.03 30nov2008 | 1 0.01 0.04 01dec2008 | 1 0.01 0.05 01feb2009 | 1 0.01 0.06 01mar2009 | 1 0.01 0.07 05mar2009 | 1 0.01 0.08 04apr2009 | 1 0.01 0.09 01may2009 | 1 0.01 0.10 01jul2009 | 1 0.01 0.11 24jul2009 | 1 0.01 0.12 31aug2009 | 1 0.01 0.13 30sep2009 | 1 0.01 0.14 01oct2009 | 1 0.01 0.15 08oct2009 | 1 0.01 0.16 31oct2009 | 1 0.01 0.17 01nov2009 | 1 0.01 0.18 28dec2009 | 1 0.01 0.19 01jan2010 | 1 0.01 0.20 01feb2010 | 2 0.02 0.22 01mar2010 | 2 0.02 0.24 31mar2010 | 1 0.01 0.25 31may2010 | 1 0.01 0.26 30jun2010 | 2 0.02 0.28 01jul2010 | 1 0.01 0.29 01sep2010 | 1 0.01 0.30 10oct2010 | 1 0.01 0.31 01jan2011 | 1 0.01 0.32 31mar2011 | 1 0.01 0.33 30apr2011 | 1 0.01 0.34 01aug2011 | 1 0.01 0.35 01aug2013 | 1 0.01 0.36 18nov2020 | 1 0.01 0.37 . | 9,963 99.63 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 18 Dec 2015