US Markets

Investors should watch this level: Art Cashin

Cashin: The ETF impact

The stock market slid Monday, leading Wall Street to wonder whether the losses will continue and to what degree. To veteran trader Art Cashin, though, technical indicators will suggest the market's next move.

Cashin, director of NYSE floor operations at UBS, told CNBC on Monday the Nasdaq has found support at the 4,087, 4,091 level. "If we roll over and break that, you might get some acceleration," he said on "Squawk on the Street."

The on Friday thrice failed to break through resistance of 1,897, Cashin noted. After its third attempt, the index broke through its lows and the broader market "all caved in together," he said.

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The market's direction is also impacted by the popularity of exchange-traded funds, Cashin said. ETFs allow investors to buy a basket of stocks, generally in a specific sector or industry, under a single stock ticker. The Select Sector Financial or XLF, for example, is an ETF for bank stocks.

"People underestimate the impact of the ETFs," Cashin said, because people tend to dump out of ETFs when the stock market falls.

The stock market will also be influenced by the release of first-quarter earnings results, Cashin said. Earnings season begins after Tuesday's closing bell, with aluminum producer Alcoa slated to release results. Financial institutions JPMorgan Chase and Wells Fargo are also expected to report this week, as well as home furnishings retailer Bed, Bath & Beyond.

Generally speaking, "the numbers we hear are kind of dull," he said.

—By CNBC's Drew Sandholm.