(Reuters) -- Wall Street closed its best month since October on a flat note on Tuesday as weaker-than-expected economic reports surprised investors after a stream of positive data in recent months.

Based on the latest available data, the Dow Jones industrial average <.DJI> ended the session down 19.83 points, or 0.16 percent, at 12,633.89. The Standard & Poor's 500 Index <.SPX> was down 0.55 points, or 0.04 percent, at 1,312.46. The Nasdaq Composite Index <.IXIC> was up 1.46 points, or 0.05 percent, at 2,813.40.

For the month, the Dow ended up 3.4 percent, the S&P 500 ended up 4.4 percent and the Nasdaq ended up 8 percent.

(Reporting By Caroline Valetkevitch; Editing by Padraic Cassidy)