"Anything that negatively affects workforce participation — and productivity of workers — has a huge effect on our global competitiveness," said Robert Kaplan, president of the Federal Reserve Bank of Dallas.

"It's not just high volumes. It's completely off the scales of what was thought was possible in an economic downturn," says one official.

Jobs report caps a week of U.S. economic data that whipsawed stocks and sent already-low Treasury yields tumbling.

“It's clearly telling you this economy is still chugging along very nicely,” says one economist.