Americans are much less likely to get health insurance coverage through their jobs than they were just 11 years ago, according to a new report from the Robert Wood Johnson Foundation.

In 2011, 59.5 percent of Americans—159 million people—received health coverage through their employers or family members’ employers, down from 69.7 percent, or 170.5 million people, in 2000, the report found.

Rising costs have led to fewer employers offering health coverage, the authors noted. Between 2001 and 2011, the average premium for family coverage rose 125 percent, to $14,447, while the average individual premium doubled, to $5,081. Higher costs also mean that more employees decline coverage even when it’s offered: during that same time period, the average employee contribution rose from $1,526 to $3,842 for family coverage and from $435 to $1,056 for individual coverage.

“Employers continue to shoulder about the same percentage of costs for employees’ health insurance as they did 10 years ago, but everyone’s costs have increased dramatically,” Risa Lavizzo-Mourey, the foundation’s president and CEO, said in releasing the report. “That is why it is so important that people have options for purchasing affordable health insurance that meets their needs.”

The levels of employer-provided coverage varied widely from state to state, with Massachusetts having the second-highest percentage—72.9 percent—of residents covered by employer plans, just behind New Hampshire’s 73.8 percent. (Connecticut, with 70.9 percent, was fifth on the list.) The states with the lowest levels of employer-provided coverage were concentrated in the South and Southwest.