The Royal Gazette/BSX Index fell more than 8 per cent as three stocks suffered sharp falls in Bermuda Stock Exchange trading.Butterfield Bank suffered the biggest slump, falling $2.70, or 14.2 per cent, to close on $16.30 on the trading of 250 shares. The bank’s US-listed shares shot up 19.1 per cent, rebounding from huge falls over the past month. On the New York Stock Exchange, Butterfield gained $2.91 to close on $18.12.Insurer Argus Group Holdings Ltd plunged 29 cents, or 12.6 per cent, to a new 52-week low of $2.01, as 15,000 shares changed hands.Telecoms group One Communications Ltd dipped 20 cents, or 5 per cent, to close on $3.80 as 7,500 of its shares were traded.Insurer BF&M Ltd also saw trading activity, remaining unchanged on $17.50, as 4,600 shares traded.The Royal Gazette/BSX dropped 129.98 points, or 8.35 per cent, to close on 1,427.32. Trading volume totalled 27,350 shares, while turnover was $144,175.The BSX Insurance Index surged 89.43 points, or 8.42 per cent, to close on 1,151.83.