How come you are so sure that the segwit will have immediate and positive results as far as the exchange rate of BTC is concerned?
I guess it will be along the same lines as it happened with the previous halving
At first it was mostly hype, even before the actual event, and then, after some time after the halving, the real impact of the halving itself kicked in heavily (in the fall of 2016 and from then on). So it way well be the case with SegWit activation too. Once it becomes known for certain, people may turn euphoric on understanding that Bitcoin is not stagnating but in fact evolving, and that will give a boost to prices on its own