Argus Group Holdings Ltd plunged 12 percent (60 cents) on The Bermuda Stock Exchange (BSX) yesterday.The insurer traded 154 shares to close at $4.40.Fellow insurance company BF&M Ltd however rose 0.67 percent (10 cents) to $15 with 1,500 shares changing hands.Overall the Index slipped 10.13 points (0.89 percent) to 1,128.83 as 1,654 shares worth $23,177.60 were transacted.