search for: dest_wac

...; the number of passengers needs to be summed to get a TOTAL annual passenger count for each city pair. So my question is: how do I create a new table (or data frame) that selectively sums My initial thought would be to iterate through each row with the following logic: 1. If the ORIGIN_WAC and DEST_WAC pair are not in the new table, then add them to the table 2. If the ORIGIN_WAC and DEST_WAC pair already exist, then sum the passengers (and do not add a new row) Is this logical? If so, I think I just need some help on syntax (or do I use a script?). Thanks. The first few rows of data look like...