Stocks were lower in narrow trading on light volume in midday trading Tuesday. All the major benchmarks are down more than 0.25%. American consumers are feeling 'okay' about the economy. The conference board's consumer confidence index rose in December to hit 92.6, that's slightly less than expected. The reading is still an improvement from the previous month. American Realty Capital (ARCP) is gaining big in the session.The commercial real estate investment trust is up 7.5% after an activist hedge fund firm disclosed it has a 7.1% stake in the company. Shares of GoPro (GPRO) are adding about 2% after analysts at Pacific Crest raised their full-year profit estimates on strong holiday demand for its wearable cameras.