ECB's Draghi says economic risks have shifted to downside

FRANKFURT (Reuters) - The European Central Bank left its policy stance unchanged as expected on Thursday but its president Mario Draghi acknowledged risks to euro zone growth were now tilted to the downside. The euro zone economy is already suffering its biggest slowdown in half a decade, raising questions over whether the ECB will be able to increase interest rates for the first time in a decade later this year as its current guidance indicates.That guidance was left unchanged on Thursday but..