How do you solve a problem such as jobs?

HOW do you catch a cloud and pin it down?

US Federal Reserve Chair Janet Yellen goes before Congress this week to give her outlook for the economy. But with different indicators pointing in different directions, Ms Yellen will have to decide which numbers matter more than others and, just as importantly, explain her choice to the markets.

Given the still-plodding pace of recovery in the United States and Europe, it would be wiser to focus on unemployment and risk underestimating growth.

Figuring out the health of the US economy today is not an easy task. The country sits in a vast middle somewhere between the doldrums of a recession and the tailwinds of a …