"Robbyn" wrote...
The "database" range:

=OFFSET(Data!$A$2,0,0,COUNTA(Data!$A:$A),COUNTA(D ata!$1:$1))
....

That's nice.

So what do COUNTA(Data!$A:$A) and COUNTA(Data!$1:$1) evaluate to?

The only ways VLOOKUP returns #REF! errors is when its 3rd argument
evaluates to a number 1 + number of columns spanned by its 2nd argument OR
when the cell in the row matching its 1st argument in the column given by
its 3rd argument just happens to evaluate to #REF!.