Goods in transit calculation

Hi,

I'm calculating GIT=Receipt stock in transit-Issue Stock in transit

Cube=IC_C03

Some values are correct as per logic.

But the problem is as following

If the goods receipt date is end of month and it is delivered on next month.

But the users are taking GIT as its value for current month only

ex:

issue=100 07092010

receipt=100 10092010

GIT = 100-100=0(Correct)\

But

issue=100 20092010

receipt= 100 23092010

issue=0 30092010

receipt=200 30092010

GIT= 300 -100=200 (correct)

next mont it is delivered on 2nd Oct 2010

I.e receipt qty=0

issue qty =200

GIT=0-200=-200(wrong)

Hope you do the needful

Thanks

Shyam