National parks are pulling their own weight by raising $34.9 billion in 2016 for the nation's economy, Interior Secretary Ryan Zinke announced Wednesday while pitching the need for much-needed upgrades to support the parks' success.

That marked a $2.9 billion increase from the previous year, Zinke said in issuing a new economic report to mark National Parks Week.

The report showed that spending supported 318,000 jobs in 2016, created $12 billion in labor income, $19.9 billion in value-added revenues, and $34.9 billion in economic output to the U.S. economy.

Lodging provided the biggest income boost, contributing $5.7 billion to local economies and 56,000 jobs. Restaurant and bars provided the second largest contribution with $3.7 billion to economies and 71,000 jobs, the report stated.

"This report is a testament to the tangible economic benefits our parks bring to communities across the nation," Zinke said. "Visitation numbers continue to rise because people want to experience these majestic public lands."

Visitation to the parks hit 331 million in 2016, the 100th anniversary of the National Park Service. That was up 7.7 percent from 2015, the report said.

Zinke, a proud Montanan, noted that eco-tourism in his home state helped to bolster revenue with the increased popularity of Glacier National Park. News reports said trips to the glacier spiked in 2016, but at the expense of nearly overwhelming the park's facilities.

"With continued record visitation, it's time to start thinking about accessibility and infrastructure," Zinke said. "Last week, it was great to see the team at Yosemite opening up areas with new wheelchair-accessible trails. In the coming years, we will look at ways to make innovative investments in our parks to enhance visitor experiences and improve our aging infrastructure."

President Trump's proposed budget would slash Zinke's agency by 12 percent, while the parks face a $12 billion maintenance backlog.

"To ensure visitors continue to have great experiences, we will remain focused on increasing access and addressing the maintenance backlog to ensure we are on the right track for generations to come," he said.