Stocks were lower in midday trading Wednesday as investors fretted over weak consumer spending that backed up recent weakness seen in the U.S. economy over the third quarter. Walmart (WMT) was the biggest loser on the Dow Jones Industrial Average after warning of a decline in earnings next year tied to recent wage increases. The bump in wages is expected to add $1.2 billion to costs. Shares were trading at their lowest level since mid-2012. TripAdvisor (TRIP) surged on news of a booking partnership with Priceline (PCLN). As part of the deal, Priceline's hotel inventory will be available through TripAdvisor's platform. SanDisk (SNDK) climbed on talk it is exploring a potential sale, possibly to Micron Technology (MU) or Western Digital (WDC).