Karen Mills, head of the Small Business Administration, is stepping down, according to an announcement by the White House on Monday.

SBA Administrator Karen Mills announced her resignation in a letter to the agency’s staff on Monday. (KEVIN LAMARQUE/REUTERS)

The SBA Adminstrator thanked her staff in a statement earlier this morning, concluding a tenure that started with her appointment by President Obama in April of 2009. The president later elevated her position to cabinet-level status in January 2012.

Mills’s departure follows closely that of SBA Deputy Administrator Marie Johns, who announced her resignation on Thursday.

During Mills’s tenure, the SBA backed more than $106 billion in loans to small companies, including record years of more than $30 billion worth of guarantees in both 2011 and 2012. Mills also led a charge to streamline applications for various agency resources, launching online portals for federal contracts and disaster loan applications.

“Four years ago, when I arrived at the SBA, America’s small businesses and entrepreneurs were struggling in the face of the worst economic environment since the Great Depression – and a banking sector that was frozen,” Mills said in a letter to the staff at the SBA. “Together, we rolled up our sleeves and went to work.”

Mills tried to broaden the appeal of entre­pre­neur­ship to demographics that haven’t traditionally been prone to start new businesses, targeting women, minorities, and senior citizens — the latter of which she began referring to as “encore entrepreneurs.”

“Over the last four years, Karen has made it easier for small businesses to interact with the federal government by reducing paperwork and cutting through red tape,” Obama said in a statement on Monday, adding that “because of Karen’s hard work and dedication, our small businesses are better positioned to create jobs and our entire economy is stronger.”

The last change under Mills’ watch came just last week, when the agency announced it would increase its available backing for surety bonds, lifting the maximum guarantee from $2 million to $6.5 million for public and private contracts.

But it wasn’t all smooth sailing for the agency these past four years. The federal government missed its stated small business contracting goals each year, and this past summer, the SBA was criticized for slow approval and delivery of disaster loans to businesses damaged by Superstorm Sandy.

Before joining the administration, Mills’ previous work was in the private sector; most notably, she was president of the MMP group, which invested in the consumer products, foods, textiles and industrial sectors.

Mills did not share any details about her plans after leaving but said she will stay in place until a successor is appointed.

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