Major indexes wavered between gains and losses for most of the day Tuesday, then ended barely in the red. Energy companies once again suffered the biggest losses as the price of oil took another tumble. Consol Energy sank 12%. Entertainment conglomerate Viacom plunged 21% after missing revenue estimates for the fifth quarter in a row. Materials companies rose. Martin Marietta jumped 9%. The Dow Jones industrial average gave up 12 points, or 0.1%, to 16,014. The Standard & Poor's 500 index slipped one point to 1,852. The Nasdaq composite edged down 15 points, or 0.4%, to 4,268. Bond prices rose. The yield on the 10-year Treasury note fell to 1.74%.