NEW YORK (CNNMoney.com) - Investors jumped back into the market in a big way Wednesday, sending the Dow Jones industrial average to a fresh six-year high amid encouraging signs of economic growth.

The Dow (up 71.24 to 11,354.49, Charts) gained about 0.6 percent to end the session at a new high for this year, marking its highest level since Jan. 19, 2000.

The broader Standard & Poor's 500 (up 3.67 to 1,305.41, Charts) index added nearly 0.3 percent, and the Nasdaq composite (up 3.33 to 2,333.63, Charts) ended modestly higher.

Upbeat corporate news and easing oil prices boosted stocks in the early going, even as the benchmark Treasury yield climbed to a fresh near four-year high.

"All indicators are pointing to strong economic growth. That's got people excited, especially in an environment of high commodity prices," Larry Peruzzi, senior equity trader at Boston Company Asset Management, said.

Investors took in solid reports on manufacturing and the real estate market that sent the benchmark Treasury yield to an intraday high of 5.13 percent -- its highest since May 2002.

Enthusiasm over the strength of the economy overpowered concerns about interest rate worries, which have been keeping stock investors on edge lately.

But inflation concerns could come back into focus Thursday, when Federal Reserve Chairman Ben Bernanke is set to testify before Congress on the economic outlook.

Investors also will be keeping an eye on earnings from No. 1 oil company Exxon Mobil (Research), which hauled in the biggest annual corporate profit on record last year. Analysts surveyed by earnings tracker Thomson Financial expect the company to post quarterly earnings of $1.47 a share, up from $1.15 in the year-earlier period.

Tech heavyweight Microsoft (Research) also is due to report its quarterly results after the market close Thursday. Analysts are looking for earnings to edge higher to 33 cents a share, up from 32 cents in same period last year.

Among stock movers, blue chips led the advance, having been hit the hardest in the recent selloff. Among Dow components, 23 out of 30 rose, led by General Motors (up $1.74 to $23.15, Research).

Merrill Lynch upgraded GM to "neutral" from "sell" on optimism about its restructuring plan, saying that there are early signs that a turnaround is brewing.

Caterpillar (up $1.02 to $75.95, Research) and AT&T (up $0.56 to $26.16, Research) were other big gainers on the Dow.

PepsiCo (up $0.36 to $57.86, Research) and Colgate-Palmolive (up $1.60 to $58.95, Research) both gained after reporting higher quarterly earnings. That gave a lift to the consumer sector.

Amazon.com (up $0.24 to $35.79, Research) edged higher after reporting earnings late Tuesday that met analysts' forecasts on sales that beat estimates. The online retailer issued a second-quarter sales forecast that sets the midpoint above analysts' estimates.

Boeing reported quarterly earnings Wednesday morning that rose from a year ago but missed forecasts. Shares of Boeing (down $0.20 to $84.91, Research), a Dow component, fell modestly after hitting an all-time high last week.

Homebuilders gained on unexpectedly strong growth in new home sales in March. The Dow Jones U.S. Home Construction (Charts) index added 1.6 percent.

Chip stocks dragged, with the Philadelphia Semiconductor Index (Charts), or SOX, losing 0.5 percent.

Market breadth was positive. On the New York Stock Exchange, winners beat losers nine to seven on volume of 1.76 billion shares. On the Nasdaq, advancers topped decliners by a narrow margin as 2.12 billion shares traded hands.

"It's one of those days where investors are looking at the strong economic news for what it says about the economy, rather than what it could mean for interest rates," said Peter Cardillo, chief market analyst at S.W. Bach & Co.

That was true of the Federal Reserve's "beige book," released at around 2 p.m. ET. The periodic report from the central bank's 12 districts showed a continued pick up in economic activity in March and early April.

Among the report's highlights: manufacturing, services and non-auto retail sales picked up in many districts versus a year ago, but higher energy costs had an impact on overall business costs, and seemed to impact tourism and consumer spending in certain areas.

Stocks slowed down a bit after the report, but remained upbeat as there wasn't anything too negative about inflation in the report, Peruzzi said.

Treasury prices tumbled on strong March reports on durable goods orders and new home sales, lifting the yield on the 10-year note to 5.10 percent, up from 5.08 percent late Tuesday. Bond prices and yields move in opposite directions.

U.S. light crude oil for June delivery fell 95 cents to settle at $71.93 a barrel on the New York Mercantile Exchange following the weekly oil inventories report. Crude hit a record trading high of $75.35 a barrel last week.

COMEX gold for June delivery climbed $8.70 to $642.90 an ounce.

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