What do you mean by forecast logic???? Provide sample table with values before and after the desired script run.
This script is also incorrect:
*XDIM_MEMBERSET ACCOUNT = RATE
*XDIM_MEMBERSET CATEGORY = ACTUAL
*XDIM_MEMBERSET TIME = 2014.TOTAL
*WHEN ACCOUNT
*IS FINAL_ACCOUNT //This condition will never happen!!!
*REC(EXPRESSION = (%VALUE%)*[ACCOUNT].[QUANTITY],[ACCOUNT].[FINAL_ACCOUNT]) //Syntax error!
*ENDWHEN