Erik Norland of CME Group said: "Investors are nervous about the combination of stretched equity valuation levels and rising bond yields."
He added: "Today's numbers could encourage the Fed to hike more quickly unless the equity market sells off in a sufficiently violent manner to convince them to downshift to a slower pace of tightening."
There are further indications wage growth could accelerate too. The National Federation of Independent Business in the US surveys its members to ask about wage plans.
Its index currently shows that almost 25 per cent of firms are planning to give pay rises, close to a record high - and this usually suggests wage growth is going to pick up soon.
Torsten Slok of Deutsche Bank said: "Historically, labour costs have been predicted with a nine-month lead by companies' plans to raise worker -compensation."
"We are now beginning to reach levels at or above previous peaks," he added.