Please can somebody help me structure my formula? I currently use the following formula to look up a value dependent on the what text is contained within cells b1 + c1. :

{=INDEX('Feb 11'!S822:S835,MATCH(example!B1&example!C1,'Feb 11'!F822:F841 &'Feb 11'!G822:G841,0))} (I'll call this formula A)

I want to edit it so that the above formula is used if both b1 + c1 contain text, but...

{=INDEX('Feb 11'!S822:S835,MATCH(example!B1,'Feb 11'!F822:F841 &'Feb 11'!,0))} (I'll call this formula B)

is used if only B1 conatins text and c1 is blank, or...

{=INDEX('Feb 11'!S822:S835,MATCH(example!C1,'Feb 11'!G822:G841,0))}

(I'll call this formula C)

is used if b1 is blank and c1 contains text.

I assume my formula will have to take the Form of: IF B1 and C1 contain text, then use formula A, If C1 is blank then use Formula B, if B1 is blank then use formula C. But I have no idea how to make this into a formula.

Can anybody please help?

Much appreciated, thank you!