Markets closed down today:
▼ Dow: -0.21 percent
▼ Nasdaq: -0.35 percent
▼ S&P: -0.23 percent
▼ Gold: down -0.19 percent to $1,559.65 an ounce
▼ Silver: up -0.59 percent to settle at $27.66
▼ Oil: -1.24 percent
Markets were down because:
With a disappointing finish on Thursday, the stock market closed what was by some measures its worst month in two years. Over five dismal weeks, Facebook fizzled, a debt crisis in Europe loomed, and nobody was in the mood to buy.
When May was mercifully over, the Dow Jones industrial average and other major indexes had erased most of the strong gains they built up through March and held on to in April.
The Wall Street adage that investors should "sell in May and go away" may not be sound strategy all the time - many financial advisers say it's foolish - but this year it looked like good advice.
The Dow lost 820 points for the month, its worst showing since May 2010. That month, investors were spooked by a one-day "flash crash" in stocks when a large trade overwhelmed computer servers.
This May, stocks limped to the finish. The Dow closed down 26.41 points on Thursday to end the month at 12,393.45. It declined on all but five of 22 trading sessions.
The Standard & Poor's 500 index dropped 2.99 points to close at 1,310.33. It fell 6.3 percent in May, its worst month since September. The Nasdaq composite index fell 10.02 points to 2,827.34, and had its worst month in two years.
On Thursday, investors latched on to a sliver of good news in the morning: May sales from retailers like Target and Macy's looked healthy, and sent stock futures higher.
Then the government offered two unpleasant pieces of economic data. The number of people applying for unemployment benefits rose to a five-week high, and economic growth from January through March was slower than first thought.
Underscoring the crisis in Europe, the head of the European Central Bank, Mario Draghi, told European leaders that the setup of the 17-country euro currency union was unsustainable "unless further steps are taken."
The Dow was down as much as 103 points and up as much as 70 before ending slightly lower. Energy companies were the worst performers for the day and the month. The price of oil, which ended April at almost $105, ended May at $86.53.
The month's most spectacular market blunder was Facebook, which debuted on the Nasdaq exchange May 18 at $38 a share. By Thursday's close it had fallen more than $8 from there.
The stock's first day was complicated by technical problems at the Nasdaq, and questions later emerged about whether Morgan Stanley, which helped take the company public, had offered some clients better information about the stock.
JPMorgan Chase stock lost 23 percent of its value during the month after the bank disclosed a surprise trading loss of $2 billion or more - a black eye for CEO Jamie Dimon, who has built a reputation as a master of risk management.
Then there was Europe. Troubles in Greece dominated headlines for much of the month, but Spain has been the market's albatross this week. It will have to spend almost $24 billion to bail out one of its biggest banks.
There is still no agreement over how to solve the crisis: Stronger countries like Germany want governments to cut spending, but voters in weaker countries like Greece have shown they are in no mood for more fiscal pain.
On Thursday, the European Union demanded that Spain provide more details about how it plans to finance the overhaul of its banking sector.
Spain's key stock market index was flat, while Greece rose nearly 3 percent. Borrowing rates for Spain fell somewhat, suggesting investors were feeling a little better about that country's finances.
Strauss said he advised clients to take money out of stocks in early spring, when the S&P was above 1,400, or about 90 points higher than where it closed Thursday.
Strauss expects the index to return to 1,385 before the year is over, though he cautioned those gains might not last.
May's results are a familiar template. In both 2010 and 2011, the market rose for several months before falling in May because of concerns about debt in Europe.
Linda Duessel, market strategist at Federated Investors in Pittsburgh, argued that this May's declines were only natural after the run-up at the beginning of the year.
The Associated Press contributed to this report.