Frequencies for first 10,000 rows of exp_dt_num variable in drug2004q1 dataset : Expiration | date of the | drug. | (YYYYMMDD) | Freq. Percent Cum. ------------+----------------------------------- 01jan2001 | 1 0.01 0.01 31mar2002 | 1 0.01 0.02 01feb2003 | 1 0.01 0.03 01apr2003 | 1 0.01 0.04 30may2003 | 1 0.01 0.05 30jun2003 | 1 0.01 0.06 01aug2003 | 1 0.01 0.07 09sep2003 | 2 0.02 0.09 28dec2003 | 1 0.01 0.10 30dec2003 | 2 0.02 0.12 01jan2004 | 1 0.01 0.13 31mar2004 | 1 0.01 0.14 01may2004 | 1 0.01 0.15 31may2004 | 2 0.02 0.17 01jun2004 | 2 0.02 0.19 29jun2004 | 1 0.01 0.20 30jun2004 | 2 0.02 0.22 01jul2004 | 2 0.02 0.24 31jul2004 | 2 0.02 0.26 01aug2004 | 1 0.01 0.27 25aug2004 | 1 0.01 0.28 31aug2004 | 4 0.04 0.32 22sep2004 | 1 0.01 0.33 30sep2004 | 4 0.04 0.37 01oct2004 | 3 0.03 0.40 07oct2004 | 1 0.01 0.41 11oct2004 | 1 0.01 0.42 31oct2004 | 4 0.04 0.46 01nov2004 | 1 0.01 0.47 05nov2004 | 1 0.01 0.48 08nov2004 | 1 0.01 0.49 09nov2004 | 1 0.01 0.50 30nov2004 | 1 0.01 0.51 01dec2004 | 2 0.02 0.53 03dec2004 | 2 0.02 0.55 31dec2004 | 4 0.04 0.59 01jan2005 | 2 0.02 0.61 31jan2005 | 4 0.04 0.65 01feb2005 | 4 0.04 0.69 28feb2005 | 1 0.01 0.70 01mar2005 | 4 0.04 0.74 04mar2005 | 1 0.01 0.75 31mar2005 | 1 0.01 0.76 01apr2005 | 3 0.03 0.79 30apr2005 | 1 0.01 0.80 01may2005 | 2 0.02 0.82 01jun2005 | 6 0.06 0.88 01jul2005 | 5 0.05 0.93 30jul2005 | 1 0.01 0.94 31jul2005 | 1 0.01 0.95 01aug2005 | 9 0.09 1.04 31aug2005 | 1 0.01 1.05 30sep2005 | 1 0.01 1.06 01oct2005 | 2 0.02 1.08 01nov2005 | 3 0.03 1.11 01dec2005 | 2 0.02 1.13 01jan2006 | 1 0.01 1.14 31jan2006 | 2 0.02 1.16 01mar2006 | 1 0.01 1.17 01apr2006 | 1 0.01 1.18 30apr2006 | 1 0.01 1.19 01may2006 | 1 0.01 1.20 19may2006 | 2 0.02 1.22 01jun2006 | 3 0.03 1.25 31jul2006 | 1 0.01 1.26 30apr2008 | 1 0.01 1.27 01jun2009 | 1 0.01 1.28 . | 9,872 98.72 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 18 Dec 2015