For the third day in a row, the stock market is marching into uncharted territory as optimism about the U.S. economy appears to be ramping up. Weekly jobless-claims figures aren't generally important enough to move the markets, but as the latest in a long series of favorable readings on the health of the economy, today's drop of 7,000 took the four-week average of claims to its lowest level in five years. In response, the Dow Jones Industrials (DJINDICES:^DJI) moved once more to record highs, climbing 49 points, or 0.34%, as of 10:55 a.m. EST. The broader markets saw somewhat more muted gains, with the S&P 500 rising just 0.2%.

Boeing (NYSE:BA) was the Dow's biggest gainer, rising 3.4% on news that the National Transportation Safety Board will release what it's calling an "interim factual report" this morning on the aircraft maker's 787 Dreamliner. With the Dreamliner having been grounded for weeks, Boeing has been under close scrutiny from both government regulators and investors. Given how important the Dreamliner is to Boeing's overall future, today's move indicates just how much investors want resolution to the lingering problem.

Beyond the Dow, truck-maker Navistar (NYSE:NAV) climbed 23.5% after announcing earnings. The company posted a loss for the quarter and fell short of expectations on revenue, but the bottom-line loss wasn't as bad as investors had expected. More importantly, Navistar now believes it will see its market share start to rise in the second half of the year, and its ongoing efforts to cut costs have borne substantial fruit, with cash balances well above the company's previous projections. The company also named a new CEO, promoting COO Troy Clarke to the position in a move that should ensure stability and continuity in its recovery plans.

Finally, Green Mountain Coffee Roasters (NASDAQ:GMCR.DL) gained 4.3% as the company entered into a K-Cup deal with Unilever (NYSE:UL) to offer the popular Lipton tea brands for Green Mountain's Keurig single-cup brewers. Green Mountain has done a good job of getting licensing agreements with major brands, and picking up Lipton should help it stay up to speed in the increasingly important tea segment.

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