The Bermuda Stock Exchange ended the week down 20.60, or 1.78 percent to finish at 1,153.26Butterfield declined 5 cents, or 3.4 percent, to $1.40 as a total of 66,480 shares changed hands.BF&M ended the week up 3.1 percent at $16.75, as 7,600 traded.Ascendant Group fell 5 cents to $11.50 on a volume of 4,900