Incorrect Sales Tax calculation on PO

I have created a PO in which header I have marked Prices Incl. Sales Tax, but still if net price of Purchase order is 100 and Sales Tax is marked 5% , Vendor is getting Credited by 100 and my Purchase Expenses are getting debited by 105. (US tax rules is marked in GL parameters). Use Tax is marked for Sales Tax group.

What I want is that Vendor should be credited by 95 and total purchase expenditures be 100. Am I missing any thing in setup.