STOCKS FALL: Here's what you need to know

Stocks lost ground to start the week as the blue chip Dow index suffered the biggest losses, falling more than 0.6% as markets were still taking stock of headlines out of Greece over the weekend and suggested little progress had been made between Greece and its EU creditors.

First, the scoreboard:

• Dow: 17,734.4, -90, (-0.5%)
• S&P 500: 2,047.6, -7.8, (-0.4%)
• Nasdaq: 4,729.6, -14.8, (-0.3%)

And now, the top stories on Monday:

1. It's been a volatile year for stocks. Year-to-date, each of the major stock averages are slightly in the red, but the real story has been how rocky of a road it's been to this point. In an email, the NYSE's Rich Barry wrote that Monday marked the 26th trading day of the year, and almost served as the 18th time that the Dow moved up or down 100 points or more. Talk about ups and downs.

2. We're still in the heart of fourth quarter earnings season, and while earnings per share have come in a bit better than expected, revenue expectations for the S&P 500 in 2015 are now flat compared to the prior year. In a note to clients, Goldman Sachs' David Kostin wrote that, "Consensus now forecasts 0% S&P 500 sales growth in 2015 following a 5% cut in revenue forecasts since October. Low oil prices along with FX headwinds and pension charges have weighed on 4Q EPS results and expectations for 2015."

3. We're still digesting the fallout from the RadioShack bankruptcy filing last week. Over the weekend, we highlighted the complete list of RadioShack stores set to close by the end of March. And Business Insider's Ashley Lutz noted on a Monday, a report in The Wall Street Journal suggested that the decline in RadioShack could, as much as anything, be tied to the decline in leisure time for the American worker.

4. Oil is still at the top of the market's mind, and in a note to clients on Monday, Citi's Ed Morse said that West Texas Intermediate crude oil prices could fall as low as $20 as the oil market still looks to balance supply and demand. "It's impossible to call a bottom point," Morse wrote. On Monday, WTI continued its recent upswing, adding another 2% to move back towards $53 a barrel.

5. Companies in the oil and gas space continue to deliver bad news to the market, with oil company SandRidge reportedly set to announce a 75% reduction in its oil rigs, according to a report from Reuters. Reuters reported that SandRidge will implement these cuts through early April, and comes after the company's stock has fallen by about 70% over the last year.

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