(CNN) As the government shutdown nears the end of its second week, around 800,000 federal workers remain out of work or working without pay. Tens of thousands of people working for federal contractors are out of work as well.
Here's a closer look at some of the numbers behind what is shaping up to be one of the longest government shutdowns in American history:
Since Democrats are taking control of the House and it is officially the 116th Congress, this is the first time a government shutdown has extended into two different sessions of Congress. On January 3, at 13 days, it becomes the fourth longest shutdown in American history. The longest shutdown came during the Clinton administration and it lasted 21 days.
President Donald Trump and former President Jimmy Carter are the only presidents to oversee government shutdowns while their party controlled both chambers of Congress.
They are also the only two presidents to oversee three shutdowns in the same year. The federal government experienced three funding lapses under Jimmy Carter in 1977 when both chambers of Congress were Democratic. The current federal shutdown is the third one this year, although the previous two were much shorter.
The money that Congress and Trump are fighting over -- $5 billion for the border wall -- is a small fraction of the overall federal budget. The total federal budget is $4.4 trillion, but 70% of that is mandatory spending. The other 30% is discretionary spending that lawmakers appropriate each year. This is where funding for federal agencies comes in.
This year, discretionary spending for federal agencies was not passed in one single 'omnibus' spending package like it has been in the recent past. Some agencies, like the Defense Department, had their funding bills passed before the end of 2018. Each agency has a separate appropriations process. 2018 was the first year in more than a decade that some of the congressional appropriations bills were passed on time. That's why only certain agencies are shut down.
Approximately 380,000 federal employees are furloughed, meaning they cannot go to work and are not being paid, according to Democrats on the Senate Appropriations Committee. Four hundred and twenty thousand federal employees are working in what the government deems essential positions and are required to continue working without pay.
Tens of thousands of employees working for federal contractors are impacted by the shutdown as well, according to Professional Services Council Executive Vice President and Counsel Alan Chvotkin. PSC is an advocacy organization that represents government technology and professional services federal contractors.
In past shutdowns, Congress has passed legislation to pay back federal employees for the time they were not paid during the shutdown. People working for federal contractors, however, may not receive the same back pay that full time federal employees do.
It is nearly impossible to nail down a specific number of how many federal contract employees are impacted by this shutdown. The impacts of the shutdown vary by department and agency, and there is no central database of stop work orders from agencies to contractors or how many affected contractors are impacted by those orders. The impact of the shutdown also changes as the shutdown continues because some work that could continue originally with other funds may no longer be able to do so, according to a PSC spokesperson.
Agencies and departments impacted by the shutdown include some of the key federal government services, like law enforcement, travel screening and business services, although many of those workers, like FBI special agents and TSA screeners, will continue to work without pay for the moment.
The agencies involved in the shutdown include the Departments of Justice, Treasury, Commerce, Agriculture, Homeland Security, Interior, Transportation and Housing and Urban Development. Part of the State Department are also closed. Other key federal institutions like the Environmental Protection Agency, NASA, the Smithsonian museums, including the National Zoo in Washington, DC, are also affected.
Many of the closed agencies provide key law enforcement functions. Homeland Security houses the Transportation Security Administration, US Immigration and Customs Enforcement and Customs and Border Protection. The Justice Department houses the FBI and a significant portion of both of these departments are essential employees working without pay.
But federally-run museums and national parks have been shut down.
And IRS workers have also been furloughed. They were already scrambling to deal with the new tax law. Tax day has been delayed after at least one previous government shutdown, but it's not clear if that will happen now. It's also not clear when this partial shutdown will end.