The U.S. Department of Homeland Security is on track to deport the fewest number of undocumented immigrants since 2007 as President Barack Obama has eased deportations by 20 percent.

The U.S. Immigration and Customs Enforcement, the DHS agency responsible for deportations, sent home 258,608 immigrants between Oct. 1, 2013, and July 31, 2014. The number of deportations during the 2014 fiscal year represents a decline of nearly 20 percent. During the same period in for the 2013 fiscal year, ICE conducted 320,167 deportations.

Based on federal figures obtained by The Associated Press, ICE deported 344,624 people during a 10-month period in 2012. In comparison to 2014 data, the rate of deportation slipped by 25 percent.

While Obama delayed an execution action on immigration, he has noted the rate of undocumented immigrants crossing the U.S.-Mexico border has declined. Throughout his presidential term, the Obama administration has deported more than 2.1 million immigrants.

The causes for the 20 percent decline may vary. Since summer 2011, the Obama administration has focused on deporting immigrants with criminal records or who may pose a national security threat. Meanwhile, many other undocumented immigrants apprehended be law enforcement are still being processed in the federal immigration court system. The immigration court system, however, has encountered backlogs. According to the Transactional Records Access Clearinghouse at Syracuse University, the national immigration court system has a backlog of over 400,000 cases as of August. One immigrant's case may take "several years" for a judge to issue a final order to stay or leave the U.S.

While more people from Central America migrated to the U.S., it has resulted in overcrowded detention facilities. The AP noted the lack of space at the detention centers led the DHS to "release many people into the U.S. interior with instructions to report back to authorities later."

According to ICE spokeswoman Gillian Christensen, ICE has formally released the rate of deportations for the 2014 fiscal year while officials are "still assessing a number of factors that inform ICE's ability to remove individuals."

"ICE remains focused on smart and effective immigration enforcement that prioritizes the removal of convicted criminals and recent border entrants," Christensen said via the AP.

DHS' Customs and Border Protection apprehended 66,127 unaccompanied children since the start of the 2014 fiscal year to Aug. 31. The rate of Mexicans crossing the U.S. border has declined as CBP agents encountered 14,702 unaccompanied undocumented minors. Migrants from El Salvador, Guatemala and Honduras are ahead of Mexico. The overall increased rate of unaccompanied minors entering the U.S. this summer was one reason for Obama to delay his executive action decision.

Obama said DHS Secretary Jeh Johnson has provided the "ground work" for the presidential executive action by presenting preliminary ideas, adding, "What I want to do is when I take executive action, I want to make sure it's sustainable ... I'm going to act because it is the right thing for the country, but it's going to be more sustainable and more effective if the public understands what the facts are on immigration, what we've done on unaccompanied children and why it's necessary."

The White House previously noted 150,000 unaccompanied undocumented children are estimated to cross the U.S. border by 2015.