Frequencies for first 10,000 rows of exp_dt_num variable in drug2006q2 dataset : Expiration | date of the | drug. | (YYYYMMDD) | Freq. Percent Cum. ------------+----------------------------------- 01jun2004 | 1 0.01 0.01 30apr2005 | 1 0.01 0.02 01nov2005 | 1 0.01 0.03 15feb2006 | 1 0.01 0.04 01jul2006 | 1 0.01 0.05 01oct2006 | 1 0.01 0.06 14nov2006 | 1 0.01 0.07 24dec2006 | 1 0.01 0.08 31jan2007 | 2 0.02 0.10 17feb2007 | 1 0.01 0.11 10mar2007 | 1 0.01 0.12 31mar2007 | 1 0.01 0.13 30apr2007 | 1 0.01 0.14 01jun2007 | 1 0.01 0.15 07jul2007 | 1 0.01 0.16 31jul2007 | 1 0.01 0.17 01aug2007 | 2 0.02 0.19 31aug2007 | 2 0.02 0.21 01sep2007 | 5 0.05 0.26 31oct2007 | 1 0.01 0.27 31dec2007 | 1 0.01 0.28 01jan2008 | 2 0.02 0.30 29feb2008 | 1 0.01 0.31 31mar2008 | 1 0.01 0.32 31may2008 | 1 0.01 0.33 05jun2008 | 1 0.01 0.34 27jun2008 | 1 0.01 0.35 01aug2008 | 1 0.01 0.36 30sep2008 | 1 0.01 0.37 30may2009 | 1 0.01 0.38 01jun2009 | 1 0.01 0.39 31aug2009 | 1 0.01 0.40 30sep2009 | 1 0.01 0.41 01sep2010 | 2 0.02 0.43 . | 9,957 99.57 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 18 Dec 2015