Butterfield Bank traded 13,017 common shares on The Bermuda Stock Exchange (BSX) yesterday.The bank closed the day at $1.28.It also saw 50 preference shares change hands, but its share price held firm at $1,230.Overall the Index was unchanged at 1,141.06 with 13,017 shares worth BD$16,664.10 and 50 shares worth US$61,866.67 transacted.The BSX Insurance Index, however, dropped seven points (0.77 percent) to 898.