retro caluculation

hello to all,

in our company if any changes happend in previous period master data retro is caluculating on the year last period ,but we need that retro calculation in the coming month it self

ex :basic pay 3000 in ,i have changed in the month 3500 fom january on words in the april

the retro calculation in the month april should be 1500, but

my schema is showing nothing in the month april

it is showing def from preveous period 6000 in the 12 th month

what changes i need to do in schema

please guide me on this issue

My schema is

000010 BLOCK BEG Retroactive accounting INTERNATIONAL

000020 COM Retroactive accounting

000030 IF O Original payroll?

000040 PDT X041 GEN NOAB Provide differences received

000050 ELSE Retroactive accounting now

000060 ACTIO X048 Reset BTEX YUI950925

000070 LPBEG RC Loop over old results

000080 IMPRT O Imports last payroll

000090 ACTIO X048 * Reset BTEX YUI950925x

000100 PORT X042 GEN NOAB Form differences and transfer

000110 COM wage types that cannot be revised

000120 PIT X047 Summary of New Payment Amount

000130 PIT X043 * new amount to data medium YUI950925

000140 BTFIL Transfer BT from last payroll

000150 LPEND End of loop

000160 IF LPRC Did the program run through the loop?

000170 PIT X043 new amount to data medium YUI950925

000180 ELSE No

000190 PIT X047 Summary of New Payment Amount

000200 PIT X043 Write new amount to data medium

000210 ENDIF re.: Did program run through the loop?

000220 ENDIF End of retroactive accounting

000230 BLOCK END Retroactive accounting