Aberdeen tips EM firms with widening margins

A country’s gross domestic product is a notoriously poor proxy for stock market returns, so last year’s 30% growth in the S&P500 – achieved while the US economy grew by 1.9% – has left investors scratching their heads. Some of the gains were achieved by share buy-backs, and irrational exuberance may also have played a role. But at the core of the US story has been firms’ ability to widen margins, producing healthy earnings growth despite modest increases in sales. Since 2010…