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Use the code below to create the calculated variable. Remember this ignores year!
On Expression tab:
function main() {
if (isNull(V1)) { // check to make sure the date field exists
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var myMonth = V1.getMonth();
return myMonth;
}
}
On the Pick List tab:
List months 0 to 12 (e.g., 0 = January, etc.; 12 = "Missing Date")
Exclude Previous Years Approach:
Modify the picklist options to include: 12 = Previous year, 13 = Missing date
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