Summary statistics for icd2ccesrd12xw2009 dataset : by Jean Roth , jroth@nber.org , 12 Jan 2016 Variable | Obs Mean Std. Dev. Min Max -------------+--------------------------------------------------------- icd | 0 cc | 0 icdvers | 2,880 9 0 9 9 modtype | 0 modvers | 2,880 12 0 12 12 -------------+--------------------------------------------------------- year | 2,880 2009 0 2009 2009 by Jean Roth , jroth@nber.org , 12 Jan 2016