Shares of Butterfield Bank improved $1.50, or 6.4 per cent, to $25 on The Royal Gazette/BSX Index after 1,146 were traded.On the New York Stock Exchange, the bank’s shares were up 31 cents, or 1.27 per cent, at $24.81.The Royal Gazette/BSX Index was up 67.46 points, or 3.83 per cent, at 1,827.31, while the BSX Insurance Index was up 12.54 points, or 0.93 per cent, at 1,355.16.