US oil fell 3.1% to $39.62 today, but has mostly hung near $40 for the last month. So why did energy stocks suffer another severe meltdown? Thurs:

Phillips $PSX -7.8%
Marathon $MRO -7.1
Conoco $COP -6.6
$EOG -6.5
Occidental $OXY -5.8
Chevron $CVX -4.2
Exxon $XOM-4.1

S&amp;P500 -0.6