How to work out the subtraction operation with 3 wage types in PCR

Dear,

We need some guides to work out the subtraction operation with some wage types in PCR, will be appreciated to get you guys' great help on this.

Our senarios is that: we have some wage types, 4000, 4040, and 4067, the calculation formula should be like below:

the amout in wt4067 = wt/101 - wt4000 - wt4040. (get the amount in /101 first, then minus 4000, and then minus 4040, finally store to wt4067 in RT).

We tried as below command lines:

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*

/101

AMT-& 4000

AMT-& 4040

ADDWTE4067 RT

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The calculation result is that: line 1-2 and line 5 worked, but line 2-3 (AMT-& 4000 and AMT-& 4040 didn't work).

We also tried with command something like AMT- 4000 or AMT+ 4000, neither worked, it seems the AMT did not get any value from wt4000 and wt4040, no matter subtraction or add operation...and those 2 wt should be already in IT?

We are stunk here and really need some one's great help. Thanks in advance.

-Weikko