Butterfield Bank shares rose 3.1 percent last week to propel the Bermuda Stock Exchange to a positive five days of trading.The bank climbed four cents to $1.34 as 22,992 shares changed hands. Butterfield’s preference shares also rose by $1, or 0.1 percent to close the week on $1,236 as 13 shares traded.The biggest climber of the week was Watlington Waterworks Ltd, which jumped 26.8 percent, or $2.95, to $13.95, as 2,100 of its shares changed hands.Insurance rivals Argus Group Holdings Ltd and BF&M Ltd both fell. Argus slipped 3.2 percent to $4.60, as 200 shares were exchanged, while BF&M fell two percent to $14.60 as 2,500 shares were traded.Telecommunications group KeyTech Ltd fell 2.4 percent to $6.05 as 5,100 shares were exchanged.The Royal Gazette/BSX Index rose 15.09 points, or 1.29 percent, over the week to close on 1,164.76.