The number of detentions for undocumented migrants attempting to cross over the southern U.S. border dropped to its lowest level in more than four decades last year.

According to Fox News Latino, Homeland Security Secretary Jeh Johnson said only 480,000 people were detained in 2014, a drastic fall off compared to Fiscal Year 2000, when an all-time high of 1.6 million immigrants were arrested for such crimes.

"These numbers are no doubt partially due to economic conditions and trends in the U.S., Mexico and Central America but also due to the very large investment this nation has made in border security over the last 15 years," Johnson said while speaking at the Woodrow Wilson Center.

Johnson also laid out the administration's goals for 2015.

"We are taking steps to fix our broken immigration system. ... Some say we should have waited for Congress to act," he explained. "Let's not forget that we did wait, for years, and Congress did not act."

In late November during a prime-time address, President Barack Obama announced details of an executive action that could spare some 4.4 million undocumented immigrants from facing the lingering risk of deportation. The plan is aimed at protecting parents and those who migrated to the U.S. as children. Others with what the president deemed "longstanding ties" to the community would also be spared.

"President Barack Obama continues to urge Congress to finish the job and pass a comprehensive, bipartisan immigration bill," Johnson said. "He is willing to work with any serious partner -- Democrat, Republican or Independent -- who wants to fix the system."

Earlier this month, House Republicans continued to advance a bill they hope will strip away the president's actions. Some GOP members are even threatening not to fund the Department of Homeland Security if their demands are not met.

Recently, House Speaker John Boehner pledged to fight the president's order "tooth and nail."