Stocks are fast approaching a level that would trigger a 'wave of selling,' UBS warns

The S&P 500 is headed towards a level that would trigger a "wave of selling," according to technical analysts at UBS. 
They forecast that the next leg down in stocks could begin as soon as next month. 
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The S&P 500 is headed towards a level that would prompt a new wave of selling, according to technical analysts at UBS. 
Michael Riesner and Marc Müller said in a note Wednesday that the 2,580 mark became an even more importa