Insurer Argus Group Holdings Ltd was the biggest climber on the Bermuda Stock Exchange last week, climbing 5.5 percent during the five days of trading.Argus’s share price rose 20 cents to $3.85, as 30,000 of its shares changed hands.Ascendant Group Ltd, owner of electricity company Belco, also had a positive week, gaining 24 cents, or 2.1 percent, to close at $11.75 on Friday, as 2,620 of its shares traded.Insurer BF&M Ltd also made gains, climbing five cents, or 0.3 percent, to $16.05 on the trading of 8,400 shares.Bermuda Aviation Services was the only domestic-board stock to fall last week, falling ten cents, or 2.8 percent, to close the week on $3.50 after 10,000 shares were exchanged.Butterfield Bank, the most heavily weighted stock on the index, was unchanged on $1.27 as 14,820 shares traded during the week.The Royal Gazette / BSX Index gained 5.61 points, or 0.51 percent, to reach 1,095.69 at Friday’s close. Share volume topped 67,000 for the week, while turnover exceeded $451,000.