The

S&P 500

and the

Nasdaq Composite Index

closed at record highs as stocks enjoyed a modest advance, while

Efficient Networks

(EFNT)

skyrocketed in its trading debut.

Efficient Networks, a developer and supplier of DSL equipment, was up 36 1/8, or 240.8%, to 51 1/8. Its 4 million-share IPO was priced yesterday by

Credit Suisse First Boston

at $15 a share.

Stocks gained thanks to strong earnings news and on market-friendly inflation data.

The

Labor Department

reported the Consumer Price Index was unchanged in June, while the core CPI, which excludes food and energy prices, was up only 0.1%. According to a

Reuters

poll, analysts had expected a 0.1% increase in the overall CPI, while they had projected a 0.2% rise in the core CPI.

On the downside, the

Philadelphia Stock Exchange Forest & Paper Products Index

, which was up handsomely this month going into today, gave up a huge chunk of those gains, tumbling 3.6%.

The airline sector slumped, led lower by

US Airways

(U)

, which warned in a filing with the

Securities and Exchange Commission

that profits in the second half of the year will fall below Wall Street estimates. It was down 3 7/16, or 7.8%, to 40 7/8. The

American Stock Exchange Airline Index

fell 1.3%.

On the

New York Stock Exchange

, advancers beat decliners 1,827 to 1,054 on 802.5 million shares. On the

Nasdaq Stock Market

, winners beat losers 2,267 to 1,715 on 1.11 billion shares.

On the NYSE, 131 issues set new 52-week highs while 33 touched new lows. On the Nasdaq, 215 issues set new 52-week highs while new lows totaled 33.

On the Big Board,

America Online

(AOL)

was most active, with 17.4 million shares changing hands. It was down 2 1/8 to 120 7/8.

On the Nasdaq,

Intel

(INTC) - Get Report

was most active, with 23.5 million shares changing hands. It was down 5/16 to 67 11/16.

Market data above are preliminary. Updated numbers and analysis will follow in the Market Roundup

Earlier...

3:05 p.m.: Stocks Post Solid Gains on Friendly Inflation Data

Major market barometers strode into the final hour of trading enjoying solid gains, buoyed in part by market-friendly inflation data.

1:57 p.m.: Benign Inflation Data Continue to Buoy Stocks

With another benign inflation report under their belt, major market averages continued higher this afternoon.

1:04 p.m.: Midday Musings: No Big Excitement Follows CPI as Market Awaits a Spark

12:04 p.m.: Stocks Cling to Modest Gains but Treasury Market Slips Into the Red

Major market averages were higher late this morning, while the 30-year Treasury bond slipped underwater.

10:51 a.m.: S&P 500 Leads Climb After Market-Friendly CPI Data

Compliments of a market-friendly report on inflation, stocks and bonds advanced this morning as the

S&P 500

was leading the market's major gauges on the upside.

10:00 a.m.: Stocks Open Higher After Flat CPI

Stocks were higher after the

Labor Department

reported that the

Consumer Price Index

in June came in unchanged, while the core CPI, which excludes food and energy prices, was up only 0.1%.