Sum - Index, Match, Match

[psrs0810]

I am having some trouble using sum with Index, Match, Match.
My Formula is =SUM(INDEX(Sheet1!$B$1:$R$50,MATCH('July 2018'!$B10,Sheet1!$B$1:$B$50,0),MATCH('July 2018'!$O$2,Sheet1!$B$1:$R$1,0)))

I need to cross match two categories and where that information meets up, I need to sum.
Thanks

 

[Rijnsent]

Hi psrs0810,
I'm trying to understand your formula: you try to find cell C2 in the first row and B10 in Column B. Both of them can have multiple matches? Because when there is just 1 intersecting cell you'd just need a simple INDEX with 2 matches without a sum. Is that what you are looking for?
Cheers,
Koen

 

[RicardoCubed]

try this approach?

Book1
	A	B	C	D	E	F	G	H	I	J	K	L	M	N	O
1		Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
2	Paul	12	14	16	18	20	22	24	26	28	30	32	34		Paul
3	George	24	26	28	30	32	34	36	38	40	42	44	46		Jul
4	Ringo	36	38	40	42	44	46	48	50	52	54	56	58		84
5	Paul	48	50	52	54	56	58	60	62	64	66	68	70
Sheet6

Cell Formulas
Range	Formula
O4	=SUMPRODUCT((A2:A5=O2)*((B1:M1=O3)*(B2:M5)))