Lookup formula where column increments by 1 when dragging forumla vertically

[Misono]

Hoping someone might be able to assist me here. I've inherited a reporting sheet where individual sheets are set up for specific sites. In another sheet there is master data for each site, filtered as follows

Date Date Date Date Date
Site Value Value Value Value Value
Site Value Value Value Value Value
Site Value Value Value Value Value
Site Value Value Value Value Value
Site Value Value Value Value Value

The reporting sheet for each site is set up with the months listed vertically, such as

A B

Jan
Feb
Mar
Apr

Column B needs to have a lookup on the site code, and to match the correct month. I then need to paste the formula down column B in a way that will ensure it's looking up against the correct dates.

Any suggestions of the best way to go about this?

 

[LloydFinancials]

A1	B	C	D	E	F	G
2	Site	Jan	Feb	Mar	Apr	May
3	1	10	2	3	4	5
4	2	19	11	12	13	14
5	3	28	20	21	22	23
6	4	37	29	30	31	32
7	5	46	38	39	40	41
8
9	Enter Site:	3
10	Jan	=INDEX($B$2:$G$7,MATCH($C$9,$B$2:$B$7,0),MATCH($B10,$B$2:$G$2,0))
11	Feb	20
12	Mar	21
13	Apr	22

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