How the government compiles the jobs report

The unemployment rate's sharp fall in September, reported a month before the election, led some Republicans to question whether the numbers had been manipulated to benefit President Barack Obama.

Current and former officials at the government agency that prepares the report rejected such assertions. They noted that the report is prepared under tight security with no White House input or supervision.

Here are some details about how the report is compiled:

_ WHO:

The numbers are crunched by several dozen people at the Bureau of Labor Statistics. The BLS is part of the Labor Department, although it was founded in 1885 and actually pre-dates the department.

The only BLS employee appointed by the White House is the commissioner, who serves a fixed four-year term and operates independently of the White House. The job is vacant but is being handled by Acting Commissioner John Galvin, a career official who has worked at the BLS for 34 years.

President Barack Obama has nominated Erica Groshen to be commissioner. But she hasn't been confirmed by the Senate.

_ WHEN:

Census workers begin surveying households to find out how many people are unemployed several weeks before the report is released.

About a week before the report is issued, the figures are securely transmitted from the Census Bureau to the BLS. The suite of offices where the report is prepared go into "lockdown." Employees must have electronic access keys to enter the area.

The economists and statisticians working on the report are required to lock up any paper copies of the report when they're not at their desks, even to go to lunch.

A final draft of the report is completed by Wednesday morning, two days before it's released. Several committees then pore over the data to ensure its accuracy. The wording is scrutinized to make sure it's free of anything that could be seen as political spin.

The final report is sent to the White House on Thursday afternoon. Only the president, his top economic adviser and a few other officials see it then. The labor secretary doesn't find out what the numbers are until around 8 a.m. on Friday, a half-hour before their release.

_ HOW:

Roughly 2,000 Census Bureau employees survey 60,000 households to compile the data used in the unemployment rate. They do the interviews over the phone or in person.

Using the data, BLS economists calculate the unemployment rate and other figures.

A second survey is also conducted. This one focuses on businesses and determines how many jobs have been created or lost. The 141,000 businesses and government agencies that agree to participate in the survey submit their payroll information online or over the phone. A few still send it by mail.

The payroll data rolls in throughout the month. Some of it comes in after the report is released. That's a big reason the job totals are later revised.

And for those who would like to double-check the agency's work, the raw data is posted online about a week after the report is released. Many academics use the data for their own research.