The Bermuda Stock Exchange retreated 0.90 percent, closing at 1,169.19.Argus was the only changer, declining 0.05 percent, on 500 shares trading at 4.25.KeyTech Ltd and Bank of NT Butterfield Ltd were both unchanged, the utility seeing 2,000 shares move for 5.55, while the bank saw 1,800 shares change hands at 1.39.