The individual percentage grades are entered into B7:B15 and averaged in cell B28 using =IF(B7>0,VALUE(FIXED(AVERAGE(B7:B15)))*100).

This result is then referenced by a formula in another cell =VLOOKUP($B$28,$B$39:$C$140,2,FALSE)

The proper GPA is listed until the grade percentage goes below 59%. When it reaches 58%, the resulting answer becomes #N/A.

I have begun with a new spreadsheet and completely reentered the formulas by hand. I have also populated the table array (B39:C140) line by line and know that the cell formats are correct.

What am I missing?