Summary statistics for icd9dx2006 dataset : by Jean Roth , jroth@nber.org , 27 Apr 2017 Variable | Obs Mean Std. Dev. Min Max -------------+--------------------------------------------------------- dgns_cd | 0 shortdesc | 0 version | 13,367 23 0 23 23 fyear | 13,367 2006 0 2006 2006 by Jean Roth , jroth@nber.org , 27 Apr 2017