Joeyyyyyg, From experience, the character values of "01","011", and "012" are being read as the same values. If your variable is a length of 2, or your format length is 2, then SAS is truncating the format or variable values to "01" and then telling you that there is an overlap of the variables. "01","011", and "012" only work as format values if your data contains "01","011", and "012" and is 3 character positions long. I like the idea suggested by Gregg Bibb of using one format for 2011 data and another for 2013 data. Since 2011 does not have the values: '01' = 'Pre-Kindergarten' /*New Selection*/ '02' = 'Kindergarten' /*New Selection*/ you have to create a new format that converts 2011 values to 2013 formatted values. Ex: format.....'01' = '03 '02' = '04' etc... Only then can you compare 2011 rows to 2013 rows. Obviously the 2013 rows for '01' and '02' will not have matching values to any 2011 reformatted rows. I would create a new variable in the 2011 file that carries the 2013 formatted value.
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