The FTSE100 does well when the pound drops against the dollar, as about 70% of revenues generated by FTSE100 companies comes from outside the UK. When the pound

The FTSE100 does well when the pound drops against the dollar, as about 70% of revenues generated by FTSE100 companies comes from outside the UK. When the pound drops, their revenues (measured in pounds, at least) go up. The FTSE250 is down 7% over 5 days.