Reading labour-market data after a shock

In the months after an economic shock, labour-market data is at its noisiest and its most quoted. That combination invites error.

Three things that distort the early reading

• Revisions. First estimates are built on incomplete returns and are often revised by more than the change they report.
• Base effects. A sharp fall one year flatters the growth rate the next, without any underlying improvement.
• Composition. Headline employment can rise while hours fall, if part-time work replaces full-time.

None of this means the data is useless. It means a single month rarely settles a question.

A more durable reading

We prefer to look at the same series three ways — levels, twelve-month change, and hours worked — before commenting. When the three agree, the signal is usually real. When they disagree, the disagreement is the story, and it is worth understanding before writing anything down.

This is unglamorous work. It is also the difference between an evidence-based reading and a confident one.