YAHOO [BRIEFING.COM]: The worst percentage slide since February has put the S&P 500 at a one month low and just above its 50-day moving average. Volatility spiked to more than a two-month high as a result.

Stocks were under sharp pressure for the entire session, such that more than 95% of the names in the S&P 500 were in the red at almost any given time this session. The selloff initially took root with global participants who pushed out of the foreign exchanges deemed riskiest. That caused Greece's Athex Composite to fall 6.7%, Spain's IBEX to drop 5.4%, and Portugal's General Index to give up 3.8%. Those losses coupled with weakness in the U.S. caused the Dow Jones World Index to surrender 2.5% in its worst percentage drop since February.

Heightened concern in the global market sent many scurrying to the greenback for cover. That drove the Dollar Index up 1.3% in its best percentage gain of 2010. It also put the dollar just below a one-year high against competing currencies.

Strength in the dollar and a sour tone in the stock market conspired to drop the CRB Commodity Index for a 2.3% loss -- its worst loss in three months.

Oil was one of the weakest commodities as it recorded its largest single-session loss in nearly three months; crude oil contracts for June closed 4.0% lower at $82.74 per barrel.

Gold also finished lower after it gave up an early gain. The yellow metal settled with a 1.2% loss at $1169.20 per ounce.

With both stocks and commodities under stiff pressure, materials stocks were the worst performers this session. The sector surrendered 3.5%.

Health care stocks held up relatively well against the selloff. The sector shed 0.8% as Dow components Merck (MRK 35.81, +0.54) and Pfizer (PFE 17.26, +0.35) provided support after they had announced this morning better-than-expected earnings.

Near-term technical support completely came undone this session. The slide only steadied when the S&P 500 approached its 50-day moving average, which was last touched two months ago. The stock market closed just above that key line.

Volatility surged with weakness so widespread. In fact, the Volatility Index, sometimes euphemistically labeled the "Fear Gauge," was up more than 20% at its session high.

This session's action attracted plenty of participants, such that some 1.5 billion shares exchanged hands on the NYSE. That's well above the 200-day average of 1.2 billion shares.

Data was an afterthought this session as participants paid little attention to news that factory orders for March increased 1.3%, which was a surprise since the consensus had essentially called for no change, and pending home sales for March made a monthly increase of 5.3%, which is a stronger pace than the 5.0% increase that had been expected.

The CRB Commodities index fell in-line with the broader stock market this session. The 2.3% loss was led by precious metals (-2.9%) and energy commodities (-3.0%). Strength in the dollar and a global sell-off were culprits.

Crude oil futures recorded their largest single session loss in ~3 months. June Crude oil futures fell 4.0% to close at $82.74 per barrel, very near its 50-day simple moving average.

Natural gas futures were actually up this session, but did not stray far from the $4.00 level. June natural gas closed up 0.5% at $4.02 per MMBtu.

Meanwhile, June gold fell 1.2% to $1169.20 per ounce and July silver fell roughly 5% to $17.84 per ounce.

Advancing Sectors: (None)
Declining Sectors: Materials (-3.5%), Industrials (-3.3%), Consumer Discretionary (-2.9%), Tech (-2.9%), Financials (-2.7%), Energy (-2.6%), Utilities (-1.8%), Telecom (-1.7%), Consumer Staples (-1.0%), Health Care (-0.8%) DJ30 -225.06 NASDAQ -74.49 NQ100 -3.1% R2K -3.2% SP400 -2.9% SP500 -28.66 NASDAQ Adv/Vol/Dec 403/2.93 bln/2331 NYSE Adv/Vol/Dec 435/1.52 bln/2650