The Dow Jones Industrial Average held slight weekly gains even in a down day for Wall Street. The blue-chip index has increased for six weeks in a row. Benchmark indexes ended the day in the red. The number of active oil rigs in the U.S. climbed for its 15th week in 16, according to the latest Baker Hughes data. The oil rig count increased by 12, a worrying sign as traders contend with global oversupply. Former Viacom (VIA.B) chairman Sumner Redstone is stepping down from his voting role on the board, effective in February. Redstone will continue in a nonvoting role. Nintendo (NTDOY) sold off even as its smartphone game Super Mario Run rocketed up the download charts. The game was downloaded nearly three million times on its debut day on Thursday.