Macro that can Add A weeks worth of data from the day in put in a cell?

[Sonythenovice]

Hello,
A big thank you to everyone who has helped me already today, one more question if thats ok?

I have a Sheet called "Data" that hold all the sales for each salesperson on a daily basis by date,
I want a macro that can add up the sales each person has done for the week from a date i put into a cell.

So to describe my data sheet "Data"

B8:ABE8 are the dates entered as DD/MM/YYYY
B11:ABE31 is all the sales made by each salesperson,
for example Tomas is B11:ABE11
and Susan is B12:ABE12
the sales person names will always be in the same rows so it ok to assume that if Tomas is in Row 11 all the data in row 11 is for him.
I also have another tab called "Reports"

In reports down column A I have all the sales persons names starting at A11 (the names are in the same order as the "Data" tab so you can assume A11 will be Tomas, A12 Susan etc.
in Cell B8 I input a date for example 21/08/2015
I would like a macro that could look along Sheet "Data" Row 8 and Find the date that matches "Reports" B8's date, then add up each row's sales for the last 7 days including that day and insert it into Reports Column B from B11:B31

if anyone has any ideas how i can do this i'd be very greatful

Thanks

Simple Example of what I need using a few dates and a few names

Sheet DATA:

	A	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P	Q	R	S	T	U	V	W	X
8	Date	12/05/2015	13/05/2015	14/05/2015	15/05/2015	16/05/2015	17/05/2015	18/05/2015	19/05/2015	20/05/2015	21/05/2015	22/05/2015	23/05/2015	24/05/2015	25/05/2015	26/05/2015	27/05/2015	28/05/2015
	SALESPERSON												when it finds the date it will look back 7 days then add the amount for each salesperson and put the total into results sheet column B
11	Tomas	10	5	33	55	9	999	5	6	101	100	2080		0	0	0	12	11
12	Susan	123	22	44	65	10	20	10	20	10	20	10	20	10	5	22	0	7
13	John	0	0	0	0	0	23	27	50	100	200	300	100	200	300	0	121	2345

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Sheet Result:

	A	B	C	D	E	F	G	H	I
8		23/05/2015	so the macro will take the date from B8 and find it in the data sheet from row 8
			Totals Sales For Week
11		Tomas	3290
12		Susan	110
13		John	800

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