The Dow Jones industrial average and the Standard & Poor's 500 are each up more than 4 percent on the month despite Monday's performance.
The DJIA closed at 15,521.97, down 36.86 points or 0.24 percent. The S&P index closed at 1,685.33, off 14.02 points or 0.37 percent. The tech-dominated Nasdaq index closed at 3,599.14, dropping 14.02 points or 0.39 percent.
Monday's winners included Caterpillar Inc., up 1.17 percent and Verizon Communications, gaining 0.92 percent.
Seven of 30 DJIA components rose. Losses were paced by Bank of America, off 1.43 percent, Hewlett-Packard, down 1.23 percent and Chevron Corp., down 1.09 percent.
On the New York Stock Exchange, 921 issues advanced, while 2,144 declined on volume of 2.8 billion shares traded.
The 10-year treasury note fell 9/32 to yield 2.601 percent.
Japan's Nikkei index shed 3.32 percent or 468.85 points to 13,661.13.
In Britain, the FTSE 100 index added 0.08 percent or 5.46 points to 6,560.25.
In after-hours trading on the New York Mercantile Exchange, crude oil was down 18 cents or 0.17 percent to $104.52 a barrel.
Gold added $6.90 or 0.52 percent to close at $1,328.80 per troy ounce on the NYMEX Comex division while silver gained 4.9 cents to close at $19.82.
On currency markets, the euro was higher at $1.3265. The dollar fell to 97.89 yen.
On the Chicago Board of Trade, December corn was off 2 3/4 to $4.73 1/4, November soybeans were off 7 1/4 to settle at $12.21 1/4 and September wheat was up 3/4 at $6.51.