Excel 2007 : Count number of cells less than or equal to today's date

Someone please help
I am close to a nervous breakdown.

Can you tell me in SIMPLE terms how I can do the following... I have in coulm B a long list of dates in the format of dd/mm/yyy and in colum a i have todays date (set automatically by the =Now() formula) , I want to count the number of cells in column B that are less than or equal to this specfic date however each time I do it comes back errors or doesnt calculate it correctly. I have tried the countif formula but can't get it to work. I have amnually counted the lines as a control and each time the figure I get back is wrong.... Please help me!!!!!