STOCKS FALL: Here's what you need to know

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Stocks closed lower on Tuesday after some key companies on the Dow Jones Industrial Average announced earnings forecasts that were weaker than analysts had expected.

Here's the scoreboard:

• Dow: 18,179.68, -43.35, (-0.24%)
• S&P 500: 2,144.17, -7.16, (-0.33%)
• Nasdaq: 5,282.52, -27.31, (-0.51%)

1. Caterpillar lowered its outlook for profit this year. The retailer of large industrial equipment said it expected 2016 earnings per share excluding restructuring costs to be $3.25, down from an earlier projection of $3.55. "Economic weakness throughout much of the world persists and, as a result, most of our end markets remain challenged," CEO Doug Oberhelman said. The company's sales have not grown on an annual basis since 2012.
2. Under Armour shares slumped 14% after the company beat third-quarter earnings forecasts but warned about future sales growth. The retailer said it expected revenue to rise in the low 20% range during 2017 and 2018, which would be its slowest pace since 2009, according to Bloomberg. Third-quarter earnings beat as demand for Under Armour's apparel, shoes, and accessories grew.
3. 3M Co, the maker of Scotch tape and Post-it notes, is struggling to grow sales in emerging markets, and on Tuesday lowered its full-year revenue and earnings forecasts for the second time. The company now expects revenue to be flat for the year, excluding the impact of currencies, down from a prior estimate of flat-1%.
4. Home prices are still rising amid strong demand and a shortage of homes for sale. The S&P/Case Shiller report for August showed that prices in 20 major US metro areas rose 0.24% month-on-month, and 5.1% year-on-year, both more than expected. Also, the FHFA house price report showed that home prices rose 0.7% in August. "Continued inventory shortages are leading to intense competition, escalating prices and mounting buyer frustration, with the average home search over the past year taking more than four months," Zillow Chief Economist Svenja Gudell in a note.
5. The Conference Board's consumer confidence index fell to 98.4 in October from 104.1 last month, which was a post-recession high. Consumers were less optimistic about current business and employment conditions, but remained hopeful about their income prospects.

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