Stocks were all over the place on Monday, powering ahead early, before falling, rising again, then slumping. The U.S. dollar dived as the euro jumped above 1.3000 and commodity currencies rebounded from recent lows. Concerns about Europe persisted, highlighted by the increasing likelihood of a default in Greek sovereign debt.

“In our view, optimistic sentiment and lightly traded volume are the two key technical concerns that have raised an early warning flag and indicate that the trend should soon flatten,” Ari Wald, equity analyst at Brown Brothers Harriman in New York told the Reuters Thomson newsagency.

“Looking ahead to the coming weeks to months, we would be watchful for a new bull market high that goes unconfirmed by our indicators, or if volume on declining days begins to outpace volume on advancing days. This would be a signal for a more meaningful correction.”

At the close of trading Monday the Dow Jones industrial averages were down 11.66 points or 0.09% at 12,708.82. The Nasdaq Composite was down 2.53 points or 0.09% at 2,784.17. The Standard Poor’s 500 Index .SPX was up 0.62 of a point or 0.05% at 1,316.00. According to Reuters Thomson data, 15% of SP 500 companies have reported earnings, with 59% percent posting results above Wall Street expectations.

On currency markets the euro was being quoted at 1.3032 around 4pm Monday as equity markets closed. The Japanese yen edged up to 76.97 while the British pound strengthened to 1.5575. The Swiss franc rose to 0.9267. The Australian dollar rallied to 1.0534, as its New Zealand counterpart rose sharply to 0.8100. The Canadian dollar was stronger at 1.0077.