Background Info:
I am designing a new credit card form for my company and I am happy with the result. In the design I had the credit card details first because users can choose between CC and Paypal (If they choose paypal it takes them off the page and does not use any info they put in, so if this is last they would lose all that effort.) However, in the final review they decided to put the credit card details last and felt that was very important and mentioned that less than 3% use paypal.
So my question is: Which order of credit card detail and billing information produces the higher form completion rate?
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