Shares of Butterfield Bank gained 2.45 per cent in New York Stock Exchange trading.The bank gained 80 cents to close on $33.46. Butterfield last traded on the Bermuda Stock Exchange at $33.The BSX was closed yesterday for the public holiday to celebrate 170 years since the arrival of Portuguese immigrants.Last week, The Royal Gazette/BSX Index gained 146.03 points, or 6.61 per cent, closing on Friday at 2,207.58. The gains were driven by increases in the value of four stocks: Butterfield, which gained 9.6 per cent over the five days of trading; Argus Group Holdings Ltd, which gained 9 per cent; BF&M Ltd, which gained 6.7 per cent; and One Communications Ltd, which gained 2.6 per cent.