Certainly among graduate employers CS degrees are the dominant source of developers (although you do get a number of Maths/Physics/Engineers as well). Unfortunately I don't think there's any good data on it. I wrote to the minister for universities a few weeks back trying to persuade him that HESA should be collecting this data, but I haven't heard back.

The problem for companies taking people without programming experience is that it's very high-risk. If you hire someone and after training find they can't program it's very hard to fire them.