Butterfield bank shares fell 2.1 percent. or 3 cents, to finish yesterday at $1.37 on the Bermuda Stock Exchange.Some 50,000 Butterfield shares changed hands.BF&M shares also traded, closing unchanged at $16.50. Some 1,120 BF&M shares traded.Overall the BSX closed down 14.16, or 1.23 percent, at 1,141.06.