Calculate the 2017 AMT exemption amount for the following cases for a married taxpayer filing jointly, and for a married taxpayer filing separately. In addition, in an Excel formula, express your solution for Case 2 for the taxpayer who is married filing jointly. Place any parameter that could change annually in a separate cell, and incorporate the cell references into the formula.

Case ................................... AMTI
1 .................................... $150,000
2 ....................................  300,000
3 ....................................  800,000