Delta Air Lines has reported financial results for the September 2015 quarter, including adjusted net income of $1.4 billion or $1.74 per diluted share, up 45 per cent from the September quarter of 2014. “Despite currency volatility and global economic uncertainty which drove a modest decline in revenues, we expanded operating margins by over five points to 21 per cent, grew earnings per share by 45 per cent, and generated $1.4 billion of free cash flow in the September quarter as demand remains solid and fuel prices have dropped materially,” said Richard Anderson, Delta chief executive.