Petrol pump prices

Any idea why the price of petrol at the pump has hardly budged over the last two months despite the price of crude dropping by around 25%? As usual if the price of crude oil goes up so does the price of petrol almost immediately but when the price of crude comes down, incredibly the same urgency to bring down petrol prices is not there.

I note that the BBC are not pushing this question, presumably because they realise that Gordon Brown needs every penny in tax he can get.