Butterfield Bank shares were down 3.8 percent yesterday in light trading.The bank was the only company on the Bermuda Stock Exchange’s domestic board to see trading yesterday, and fell five cents to close on $1.25, as 800 shares changed hands.The Royal Gazette / BSX Index fell 23.92 points, or 2.1 percent, to close on 1,128.86. Volume was 800 shares and turnover was $1,000.The BSX Insurance Index rose two points, or 0.2 percent, to close on 1,051.www.bsx.com