I would say make this decision based on what your prefer and like more because from experience if you do what you like you can go far. But if ur still choosing I would say computing because with economics/finance you are limited to finance pretty much as a career. But with computing you have that ability to move into other careers like finance or science or research or bio research using data. The opportunities are endless but it depends on whether you like computing more otherwise do finance because you will learn a lot and be around some very interesting people too.