Blank cells returning 0 (zero) value with INDEX

I need to merge data from one worksheet to another. I am using INDEX, MATCH functions, which work fine except that when a match is found and the cell is blank, the value returned and placed in the merged cell is 0.

I want the merged cell to be blank, same value as the original cell.

Here is the function that I am using:

=IFERROR(INDEX('[worksheet_with_info_to_merge]'!$A:$T,$X2,MATCH(P$1,'[worksheet_with_info_to_merge]'!$A$1:$T$1,0)),"-")

Thanks in advance for your time.