NEW YORK (CNNMoney.com) -- Stocks tumbled Friday at the end of the Dow's worst month in 70 years, after a downgrade of Spain's debt reminded investors that Europe's economic woes continue.
The Dow Jones industrial average (
INDU) lost 122 points, or 1.2%. The S&P 500 index (
SPX) fell 14 points, or 1.3%, and the Nasdaq composite (
COMP) dropped 21 points, or 0.9%.
Stocks were already weak before the ratings agency cut Spain's debt one notch. While the cut still leaves the debt in investment grade territory, as opposed to junk, it nonetheless managed to rattle investors in a thinly-traded session.
"People were expecting a nice slow day and then the Spain news turned things around," said Joseph Saluzzi, co-head of equity trading at Themis Trading.
"It may have been anticipated, but It's still a big deal," he said. "It tells us we are not out of the woods yet."
Friday marked the end of a rough month on Wall Street in which stocks plunged on worries about the European debt crisis, the weak euro and bets that the market advance had outpaced any economic recovery.
The Dow lost 7.9%, seeing its worst month since February 2009, when it fell 11.7%, and worst May since 1940, when it plunged 21.7%.
The Nasdaq lost 8.3%, its worst month since November 2008, when it dropped 10.8%, and its worst May since 2000, when it skidded 11.9%.
The S&P 500 declined 8.2%, its worst month since February 2009, when there was an 11% loss, and its worst May since 1962, when the drop was 8.6%.
Stocks rallied Thursday after China said it will stay invested in European debt. The Dow jumped 285 points, or almost 3%, and the S&P 500 and Nasdaq both gained more than 3%.
After such an advance, investors pled exhaustion Friday, with trading pretty quiet as many market pros stepped out ahead of the Memorial Day weekend.
Stock declines were broad, with 27 of 30 Dow components falling, led by Caterpillar (
CAT,
Fortune 500), Chevron (
CVX,
Fortune 500), Exxon Mobil (
XOM,
Fortune 500), Hewlett-Packard (
HPQ,
Fortune 500), IBM (
IBM,
Fortune 500), 3M (
MMM,
Fortune 500), Johnson & Johnson (
JNJ,
Fortune 500).
The CBOE Volatility (
VIX) index, or the VIX, Wall Street's fear factor, rallied nearly 8% to 31.97.