Dr. Tom McDonnell:

That is the case when talking about changing rates but changing rates, in many respects, is not as significant as bringing in new reliefs, and things like that. If, for example, a capital gains tax rate was being changed significantly up or down, presumably that would only be changed by a few percentage points in a particular year. It would be strange to change it radically, although I acknowledge that has been done in the past. If capital gains tax is radically changed, it will create an artificial threshold point where there will be a great volume of activity right before or after that point of change. That is always going to be the case.