Tell me more on how the economy would be weaker?
I doubt other countries would miss out on the U.Ks high GDP.
the main thing i think is that there are a lot of unknowns. people don't know for sure how all this is going to turn out because it's unprecedented, and so the UK is, for the time being, a much higher-risk investment. if you don't have investment, your currency's value on the foreign exchange market is going to go down. people are going to wait and see if it's going to turn out well