Oil tumbled to its biggest weekly decline of the year after an International Energy Agency report highlighted the magnitude of the global crude glut. The IEA, an energy monitor, “>said low prices are taking a toll on supply but producers haven’t yet scaled back enough to make a dent in stockpiles. Oil has fallen for six straight sessions while registering its largest weekly percentage decline of 2015. This latest leg of oil’s selloff, which has slashed prices by about a third since the start of the year, has rattled stock and debt markets anew. The Dow Jones Industrial Average recently was down 270 points, or 1.6% . Junk bonds, which were also reeling from a fund’s closure, slumped . U.S. oil futures for January delivery fell $1.14, or 3.1%, to $35.62 a barrel on the New York Mercantile Exchange Brent, the global benchmark, fell $1.80, or 4.5%, to $37.93 […]