Excel Function SUMIF with Look up functions or Index and Match

All,

I have a set of data that looks like the following table. I want to be able to sum all the values that fall under the Alphas, Betas, X-Rays etc. for a particular specimen. I suppose the SUMIF function with INDEX and MATCH should work, however i am unable to put the formula together. Any help would be much appreciated.

Alpha Beta X-Ray Gamma Neutron
Alpha Beta Gamma Neutron Alpha Beta X-Ray Beta X-Ray Gamma Neutron Beta X-Ray Alpha Beta X-Ray Gamma Neutron Beta X-Ray Alpha Neutron Gamma
Spec A 1 2 4 3 6 12 10 8 3 12 8 9 2 6 8 5 10 7 5 8 4 10 12
Neutron X-Ray Gamma Neutron Alpha Beta Gamma Alpha X-Ray Gamma Neutron Beta X-Ray Alpha Beta X-Ray Gamma Beta Gamma X-Ray Beta Alpha Neutron
Spec B 8 9 12 7 10 4 6 7 10 7 6 8 8 1 12 5 4 8 10 3 9 8 6
Neutron X-Ray Gamma Neutron Alpha Beta Gamma Alpha X-Ray Gamma Neutron Beta X-Ray Alpha Beta X-Ray Gamma Beta Neutron X-Ray Alpha Gamma Beta
Spec C 4 4 8 7 8 10 9 12 6 1 5 2 12 8 6 12 8 10 7 4 5 12 8


Thanks

Hi Pete,

Thanks for your response. I noticed that formula isn't yielding the desired result as you drag down. For eg; Spec B, X-Ray is returned as 32 instead of 35; Spec B, Gamma is returned as 29 instead of 39 and so on. It is working alright for the first row only.

Sample file attached.

Regards,
Sontu

Len(e2)=6

len(ab6)=5

Wow! Something as small as that could stuff up a formula. Thanks for bringing it into my attention; much appreciated. It works perfectly now; not sure why i was complicating things with Index and Match lol.

Thanks to Pete too.

Cheers,
Sandeep