Butterfield Bank dropped 6.25 percent (10 cents) on The Bermuda Stock Exchange (BSX) last week.The bank traded 236,164 shares to close at $1.50.It also saw 15 preference shares change hands, but its share value held firm at $250.BF&M Ltd meanwhile rose 1.35 percent (20 cents) to $15 with 1,069 shares transacted.Other traders included KeyTech Ltd (17,300 shares), the Ascendant Group Ltd (14,900) and Polaris Holding Co Ltd (50), but all of their share prices remained unchanged.’The Index, as a whole, fell 51.45 points (4.17 percent) to 1,233.63 as 269,503 shares worth BD$678,387.05 and 215 shares worth US$20,550 were traded.The BSX Insurance Index, however, climbed 37 points (3.98 percent) to 893.