Homeland Security Secretary Jeh Johnson  (AP Photo/Manuel Balce Ceneta)

Homeland Security Secretary Jeh Johnson and his staff have made improving morale at the sprawling agency a top priority for nearly two years, boosting employee training, studying how to improve fairness in hiring and promotions, addressing what ties the diverse workforce of 22 departments together.

Yet DHS ranked at the bottom — for a fourth year running — of the 19 largest federal agencies in this year’s Best Places to Work in the Federal Government survey, released Tuesday.

[Homeland Security ranks dead last in morale — again — but Jeh Johnson’s morale is high]

Just 43.1 percent of homeland security employees say DHS is a good place work, a small dip of 0.9 percent over 2014. While 65.9 percent of those surveyed said their skills are well-matched to the agency’s mission, only 31.4 percent say they have confidence in their senior leaders, and 30.7 percent believe that promotions are based on merit.

Johnson, a former Pentagon general counsel who took the top job at DHS in December 2013, on Tuesday sent an email to the 240,000 employees who work for him expressing his frustration with the rankings.

[Good news: Federal worker morale may have bottomed out. Bad news: It’s still terrible]

“I’m disappointed,” he wrote. “We know improving employee satisfaction takes time, and we will not give up. We have an aggressive plan to do this.”

He noted that the survey, put out every year by the Partnership for Public Service and Deloitte, reflects improving morale in some corners, particularly in the Office of the Secretary and other departments at the Washington, U.S. Citizenship and Immigration Services and the Office of Science and Technology.

[DHS morale sinks further despite new leadership at the top, survey shows]

But he stressed that the public “and our own DHS workforce” need to “recognize the vital work they do to protect the homeland.” He cited some recent examples, including the response of the agency’s counterterrorism and intelligence teams to assess and respond to the attacks in Paris, San Bernadino, Calif. and the crash of a Russian passenger plane over the Sinai Peninsula in October.

But he seemed worried about the “self-fulfilling” element of surveys like these. “Continue to tell workers they are unhappy, and they believe you.”

Here’s the full text of Johnson’s email:

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