I have 2 matrices in different worksheet:

-Volume Matrix
-Price Matrix

Manual entries are performed in order to fill out both matrices.
There's one restriction: If Volume is filled out, there must be a price
too.

How Do I detect if the later condition is not been accomplished?
Is it possible to work it out using Array Formulas? Get 1 if error or 0
if it's Ok.

The structure of the matrices are as follows:

Volume Matrix
=============
Jan Feb Mar Apr .... Dec
Product 1
Product 2
Product 3

Price Matrix
=============
Jan Feb Mar Apr .... Dec
PriceProduct 1
PriceProduct 2
PriceProduct 3

Conditional formation does not work here as information is on two
separete worksheets.

Thnks