It works great with $current_month = 11. When I set $current_month = 10 I get (mth_07 + mth_08 + mth_09 + mth_10) but it should be (mth_09 + mth_10 + mth_11 + mth_12). $current_month = 9 should yield (MTH_10 + mth_11 + mth_12 + MTH_13), etc. I think we are close