URGENT:dump while substacting: BCD_BADDATA

Hi ,

i am substracting two type p values and storing it in a type p value.

w_diff = w_esbtr - w_glbal.

w_esbtr = 2000200020002.00

w_glbl = 200020003.10

it is giving me a dump "Packed field contains incorrect BCD format."

what doe it mean. how to solve it .