Is it possible to determine an airfare based on the taxes?

I purchased a package on Expedia: Airfare on AA plus 4 nights hotel, for less than half of what the airfare alone would have cost. A nice deal, IMO.

My expense accounting system, however, requires that I separate the amounts for these two items. AA.com receipt shows Fare n/a, Taxes $36.41. It's a domestic nonstop (DFW-SLC).

So, who knows how to figure out what fare amount would entail $36.41 in taxes (and fees?)?