Many of us pay close attention to the new jobs numbers each month. But the initial estimate isn't the end of the story: the BLS routinely uses new and better data to keep improving its estimates. This is good for balancing timeliness and accuracy, though it can be a little confusing in practice, and is often misinterpreted. When we learn about the annual benchmark revision this Friday, it will be important to understand what the new information does and doesn't mean.