Is there a quick way to write a lengthy IF statement?
When Excel reads a statement that returns TRUE or FALSE, these values are interpreted by the formula as 1 or 0, respectively.
Therefore, these two statements return the same result:
=IF ( ISNUMBER (A1) , B1 , 0 )
=B1 * ISNUMBER (A1)
This can be a useful trick to improve the readability and speed of writing some formulae.