Shares of Las Vegas Sands (LVS), MGM Resorts International (MGM) and other top Las Vegas casinos were down early Friday after Nevada gambling officials said statewide gambling revenue fell 12.4% in January, plunging 18.8% on the Strip, compared with January 2012. The Gaming Control Board said Sands, MGM, Wynn Resorts (WYNN), Caesars Entertainment (CZR) and others collectively took in $909.2 million for the month, down from $1.04 billion a year