Question about aggregating two measures

Not sure if measures can be used in this manner and hoping to get some advice.

I am working with income and expenses from a typical general ledger transactions table (TABLE). Each type of transaction in the general ledger table has an identification number, "GLID," with income transactions falling between GLID=40000 and 49999 and expense transactions falling between GLID=50000 and 65000.

I created a measure called "Current Income" = SUM(TABLE[CreditAmount)) - SUM (TABLE[DebitAmount]), which is filtered for the range of transactions between GLID=40000-49999. This works perfectly and the income results are as expected. I also created a measure for "Current Expenses" = SUM(TABLE[DebitAmount]) - SUM(TABLE[CreditAmount], which is filtered for GLID=50000-65000. This also works perfectly and the expense results are as expected.

What I am trying to do now is to create a measure for "Net Profit" subtracting the "Current Expenses" from the "Current Income." Logically, this would be the sum of the above two measures: SUM(TABLE[Current Income]) - SUM(TABLE[Current Expenses]). But the SUM function is looking for a column, not a measure.

I tried Net Profit = SUM(TABLE[CreditAmount]) - SUM(TABLE[DebitAmount]) filtered for the entire range of GLID numbers from 40000 to 65000, but again no luck.

So, here I am with tin cup in hand. Any help appreciated.