Extract Rule fast for Cumulative FTE

Summary:

Hello All, i am trying to write a custom FF for my hcm extract. I need to fetch cumulative FTE for the employee in all assignemnts and then display this value in my extract. I tried to wirte a ff but it doesnt take the local variable:l_current_asg_FTE=PER_ASG_FTE_VALUE and shows the error as: Formula EXT_FTE_ADP_CORRECT_DATE, line 26, the assignment uses inconsistent data types. Has anyone done something similar or can shed some light wil be really appreciated! thank you for your time

Content (required):

I tried to wirte a ff but it doesnt take the local variable:l_current_asg_FTE=PER_ASG_FTE_VALUE and shows the error as: Formula EXT_FTE_ADP_CORRECT_DATE, line 26, the assignment uses inconsistent data types. Has anyone done something similar or can shed some light wil be really appreciated! thank you for your time