Hello, I'm trying to merge two like .csv files to produce a result file from them. The key is the first 3 fields. All records that are unique will be output to the results file. All matching records (fields 1-3 are identical) will be subject to a further test. For these, I will need to determine the percent-change in the numeric values in field 4 between the two records. If the absolute value expressed as a percent change is greater than 1, then the record from fileA is output to results, otherwise record-fileB is output. Your help is much appreciated!

In reply to file merge by nraymond

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