Concerns that growing Covid-19 Delta case numbers could lead to fresh lockdowns and a more protracted economic recovery. A 7% slump in the oil price also weighed on the Energy sector (-3.6%). Airlines fell by 3.8%, Banks lost 3.3% and the Hotel and Restaurant index fell by 2.7%. Investors also brace for more earnings results this week. So far 41 of the S&P 500 index group have reported and 90% have beaten estimates according to Refinitiv. The Dow Jones index fell by 726 points or 2.1% after being down 946 points. The S&P 500 index fell by 1.6%. And the Nasdaq lost 152 points or 1.1%.