What month is that for? CT takes will vary wildly with month I'd imagine, as you'd have something like half of all companies would have December year-ends, and so would pay most of their tax in November (one month before), with the balance in the summer (the exact month has probably changed since I was in practice).
Don't forget that increasing tax could have a negative effect as well if companies up and leave because of it. Given how reluctant the Government are to change CT, I'd imagine they've possibly suggested an increase and been told where to go.