Error in Formula

[Nigel]

I am trying to add this formula in a cell to get rid of a div/0 error but it
won't let me add it

=IF(L4=0,0,IF(L20=0,0,if(l4=0 and l20=0,0,(L4-L20)/L4)))

it doesn't like the statement if(l4=0 and l20=0,0 is there anyway to
easily get rid of div/0 error

thanks

[Paul Sheppard]

Try this

=IF(L4=0,0,IF(L20=0,0,IF(AND(L4=0,L20=0),0,(L4-L20)/L4)))

Paul