In case some additional information comes in after the survey results are published for the previous month then a revision in numbers has to take place. The revised data incorporates the addition information to improve the initial estimates. You may find the some interesting analysis and data on ForexAbode @ Historical Nonfarm Payroll Data - An Insight. This also has link to another page where the revised/actual data is updated and you can find past 64 years data.
I never knew they revised nfp numbers after the fact, good to know I guess… It would be interesting to see how much they are revised from time to time.
Yep definitely interesting. The thing is though traders often react to the headline figure for the month and hardly look at the past revisions. Like the latest release for instance, the dollar weakened because the March number missed the forecast but if you look at the previous month revisions, they would more than make up for the miss. I guess the revisions would matter to longer-term traders while short-term traders pay more attention to the actual numbers on the day of the release.