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markets, click or type LIVE/ in a news window.)

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Indexes off: Dow 1.05%, S&P 500 0.87%, Nasdaq 0.79%

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Nike ( NKE ) dips on bleak revenue outlook

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Micron falls on conservative gross margin forecast

(Updates for market open)

By Pranav Kashyap and Johann M Cherian

March 21 (Reuters) -

Wall Street's main indexes declined on Friday as investors

continued to navigate the complex landscape of tariffs, with

FedEx ( FDX ) becoming the latest firm to

adjust

its annual projections due to economic uncertainties.

FedEx ( FDX ) fell 10.9%, while peer UPS lost 3.3%.

Delivery firms are often seen as a barometer for the global

economy given their involvement in a wide range of industries.

The delivery companies weighed on the Dow Jones Transport

Index, which is often seen as a gauge of U.S. economic

health. The index fell 2.1% and has lost over 19% from its

November all-time peak.

Airlines such as Delta and United also

dragged the index lower, after

Britain's Heathrow Airport was shut

, sparking global travel turmoil.

In an interview, Chicago Federal Reserve President

Austan Goolsbee

noted

that the current conditions could "maybe" a shock to the

economy.

Separately, New York Fed President

John Williams

reiterated the U.S. central bank's monetary policy stance,

given the uncertainty.

Lingering fears of a prolonged global trade war,

threatening to unravel economic stability and squeeze corporate

profits, have cast a shadow over markets.

Markets now await President Donald Trump's plans on

reciprocal and sectoral tariffs that are expected to take effect

in early April.

"We really don't know what the wild card is coming out of

Washington, and this goes for the Fed as well," said Michael

Matousek, head trader at U.S. Global Investors Inc.

At 9:54 a.m. ET, the Dow Jones Industrial Average

fell 438.68 points, or 1.05%, to 41,514.64, the S&P 500

lost 49.00 points, or 0.87%, to 5,613.89 and the Nasdaq

Composite lost 140.39 points, or 0.79%, to 17,551.24.

Materials led declines among the 11 S&P 500

sectors with a 1.7% drop.

Friday's session also marks the simultaneous expiry of

quarterly derivatives contracts tied to stocks, index options

and futures, also known as "triple witching", which added to

market volatility.

On a weekly scale, the benchmark S&P 500 index is on

track to mark its fifth-straight week in the red - its longest

weekly losing streak since May 2022.

The tech-heavy Nasdaq is on track to record its

longest weekly losing streak in nearly three years, while the

blue-chip Dow is positioned for marginal gains.

Earlier in the week, investors took some comfort from

comments of Fed Chair Jerome Powell, who said that the overall

economy was on solid footing, but warned of a cloudy outlook on

the impact from Trump's policies.

Traders are pricing in approximately 70 basis points of rate

cuts from the Fed this year, according to data compiled by LSEG.

Nike ( NKE ) slid 8.4% after the sports apparel maker projected

a sharper decline in fourth-quarter revenue than analysts had

anticipated.

Micron Technology ( MU ) fell 7.3% as the chip maker

forecast third-quarter gross margin below estimates.

Lennar ( LEN ) slid 6.6% after the homebuilder reported a

lower first-quarter profit.

Declining issues outnumbered advancers by a 4.22-to-1 ratio

on the NYSE and by a 3.1-to-1 ratio on the Nasdaq.

The S&P 500 posted nine new 52-week highs and 16 new lows,

while the Nasdaq Composite recorded 14 new highs and 116 new

lows.