Comparing Values Between Columns

Hi, I am trying to run a COUNTIFS formula that compares values in column B to column A. I want to count the rows, if in B the values therein are >= the adjacent values in A. Here is the formula I used =COUNTIFS(B:B,">="&A:A). The trick I think is that one column can't be greater than another. Is there another formula or trick that will yield what I want? I set up a simple test that should return 9. But it doesn't. Help please!
5 5
6 6
3 3
8 8
12 12
9 9
65 65
14 14
6 6
77 50
13 10
12 10

Try =SUMPRODUCT(--(B1:B1000>=A1:A1000))