Concerns about economic weakness abroad, especially in China, Italy, and the UK, appeared to outweigh a pair of strong reports on the US economy, giving stocks a tiny loss. Crude oil prices sank 3%, pulling down oil producers. Small companies, with fewer ties to the world economy, made gains. ISM’s gauge of manufacturing reached 59 in August, the highest since March 2011. And the Commerce Department said construction spending rose 1.8% in July, the most in more than two years. But signs of solid growth raise the odds the Fed will soon lift short-term interest rates, tightening its easy-money policy. Higher rates often slow stock markets.