Suppose you merged the cells of the range B2:B23 two by two, and you asked =AVERAGE(B2:B23)
Cells are never actually merged. The area of one cell just covers the others and thus hides them for the view. The cells hidden in this way may still have any content, and also numerical values. Your observation indicates that prpobably all the hidden cells contain something numerical and have the value 0. Try =COUNT(B2:B23). It may return 22, thus signaling that all the 22 cells contain a numerical entry or result.
Despite the fact that you cannot enter the hidden cells, you can use a visible cell to ask =ISNUMBER(B5
) if B5 is “merged” with B4. If you get TRUE and =(B4=0)
is also TRUE things should be as I supposed.
(Merging cells is a plague. If at all, you should exclusively use it for text. Cells made invisible by merging should always be cleared before the merging.)