It's not the average wage that tells you the health of the economy.
It's the median wage that does.
According to the Social Security Administration, the average wage in 2015, the latest year they report for, was $46,120 per year.
https://www.ssa.gov/oact/cola/central.html
But if you look farther to the right on that table, you'll see that the median wage is only about $30,000 per year. That means half of all American workers make less than $30,000 a year, and half make more.
A $46,000 average and a $30,000 median tells me that the average is being run up by a small percentage of workers that are making really big bucks while a whole lot of workers are making shit.
And that's the problem with our economy. Inequality.
And it has gotten worse under Obama. It also got worse under Bush 2 before him. And Bill Clinton before him, and Bush I before that, and Ronald Reagan before that. Both major parties are screwing over the working class and they have been doing it for decades.