Compare coulmns

[murchu]

I want to compare two coulmns and check how many duplicate vaules exsist in the sheet. Sample data is provided. What would be easiest way?

78AC080 78C7587
1CW9G11 78AC623
78AC306 78AC490
78AC311 78AC488
78AC313 78AC483
78AC401 78AC480
78AC418 78AC474
78AC419 78AC467
78AC434 78AC465
78AC441 78AC457
78AC454 78AC455
17KR90J 78AC454
78AC457 78AC434
78AC465 78AC419
78AC467 78AC418
78AC468 78AC313
78AC469 78AC311
78AC474 78AC306
78AC480 78AC291
78AC483 78AC080
78AC488 1CW9G11
78AC490 196BC11
196BC11 18LG411
78AC627 17KR90J
78C7587 15H4K0J

 

[Mark W.]

Book1
	A	B	C	D	E
1	78AC080	78C7587	20		20
2	1CW9G11	78AC623	21
3	78AC306	78AC490	18
4	78AC311	78AC488	17
5	78AC313	78AC483	16
6	78AC401	78AC480	#N/A
7	78AC418	78AC474	15
8	78AC419	78AC467	14
9	78AC434	78AC465	13
10	78AC441	78AC457	#N/A
11	78AC454	78AC455	12
12	17KR90J	78AC454	24
13	78AC457	78AC434	10
14	78AC465	78AC419	9
15	78AC467	78AC418	8
16	78AC468	78AC313	#N/A
17	78AC469	78AC311	#N/A
18	78AC474	78AC306	7
19	78AC480	78AC291	6
20	78AC483	78AC080	5
21	78AC488	1CW9G11	4
22	78AC490	196BC11	3
23	196BC11	18LG411	22
24	78AC627	17KR90J	#N/A
25	78C7587	15H4K0J	1
26
Sheet2