Trying to create a calculated column that shows the difference in a value in current row (contains a date) to the same value in the previous years (for the same date) value.
You want to use the OVER ParallelPeriod() or OVER NavigatePeriod() functions. See:
Advanced Custom Expresion:https://docs.tibco.com/pub/sfire-analyst/7.8.0/doc/html/en-US/TIB_sfire-...
If you want to post a sample data structure, I could help with more detail.
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