Wall Street ends week on a negative note amid trade war concerns

• Dow Jones drops more than 90 points on Friday.
• Falling crude oil prices weigh on the S&P 500 Energy Sector.
• Nasdaq becomes the best performing index of the week.

Major equity indexes started the day in the red on Friday after the United States announced $50 billion worth of 25% tariffs on Chinese imports and China retaliated by introducing their own tariffs of $50 billion on U.S. goods.

Commenting on Wall Street's reaction to this developments, "the market’s selling off, though not drastically, mostly on renewed fears of a trade war, maybe people are just getting used to the rhetoric and stepping off of it a little bit,” Peter Tuz, president of Chase Investment Counsel in Charlottesville, Virginia, told Reuters.

Meanwhile, crude oil prices fell sharply on Friday to erase the gains that they recorded on the first four trading days of the week as investors remain on edge ahead of OPEC meeting in Vienna, at which producers are to discuss ramping up the production levels. Moreover, Russian energy minister Novak said that Russia and Saudi Arabia both "in principle" supported a gradual increase in oil supply. The S&P 500 Energy Sector (SPNY) closed the day 2.1% lower. 

Although indexes were able to recover some of their losses in the second half of the session, they all still closed in the negative territory. The Dow Jones Industrial Average lost 90.92 points, or 0.36%, to 25,084.39, the S&P 500 dropped 3.27 points, or 0.12%, to 2,779.22 points and the Nasdaq Composite fell 14.69 points, or 0.19% to close at 7,746.35 points.

For the week, The S&P was virtually unchanged, the Dow Jones Industrial Average was down 0.89% and the Nasdaq Composite was up 1.32%.