After opening indecisively, the U.S. stock market was able to close Friday's trading session in positive territory within 1 percentage point. Concerns about the economic stability in China against the backdrop of worsening problems of construction companies, ambiguous statements about detection of new strains of COVID-19 and expectation of the end of the fiscal year, with its traditionally falling September - perhaps these are the main factors preventing the market from growing at the moment. Participants are cautious and often a day of good growth is immediately followed by a day of quite active decline.