IF statement, IFERROR or both?

Hi

First time poster!

This is probably a really basic one for most people but i'm having trouble with it. Trying to figure out a formula for the below:

IFERROR Question.jpg

As you can see I've currently got a very simple setup. In column D I've got the formula =C1/B1 and this works fine until i drag it down and get the divide by zero errors.

I'm trying to incorporate an IFERROR function so i don't have to manually change every cell that has this error, however, i want 2 different outcomes. I want to show 0% if B is zero and A is Zero and i want to show -100% if B is zero and A is more than zero.

(I know that technically there is no correct answer to dividing by zero and i don't want to get into that argument)

Can anybody help?

First of all, thank you JBeaucaire

For my understanding, am i getting this right?

IF(B1=0, this is test number 1
IF(A1=0, this is test number 2
0%, this is value if true number 1
-100%), this is value if true number 2
C1/B1) this is value if false which applies to both tests.