NEW YORK--(BUSINESS WIRE)--Fitch Ratings has increased its 2015 U.S. high yield default outlook to 2.5%-3% from 1.5%-2%, reflecting the impact that languishing oil prices, weak coal demand and burdensome regulation have had on energy and metals/mining companies during the first half of the year. 'These factors will continue to drive up the default rate into 2016 as distressed debt exchanges (DDE), bankruptcies, and missed payments take their toll,' says Eric Rosenthal, Senior Director of Levera