With the awsome blogs in this forum, I was able to get the number of months between 2 date pickers as described below:
12 * (substring(PERIOD THRU DATE, 1, 4) - substring(PERIOD FROM, 1,4)) + (substring(PERIOD THRU DATE, 6, 2) - substring(PERIOD FROM, 6, 2))
But the results I need are months in decimals and then round up if greater ...