Luckily for us, there is a very nice piece from the Cleveland Fed on these questions.
Here's a graph from the paper of the overall premium (clic the pic for an even more educational image):
Median wages for BA/BS and higher have gone from 140% of high school only wages to 180% of high school only wages from 1977 to 2010. Note that the premium for "some college" has stayed fairly flat over the same time period.
So, "go to college, young person", right? Well there is the big issue of whether higher education creates human capital or just serves as a signal of innate ability (phone call for Robin Hanson).
And there's also the issues of "what major" and "what degree".
Here's another graph from that Cleveland Fed piece (clic the pic for an even more self-serving image):
English majors get a wage premium of a bit below 1.5 and if they get an advanced degree, it's around 1.75. Economics majors get a wage premium of a bit below 2 and if they get an advanced degree, it's around 3.00
Yet the thickness of the bars tells us that there are more english majors than economics majors (of course this could have something to do with labor demand, but I somehow doubt it)!
Electrical engineering is the most remunerative major with an average premium of 2.5. Elementary Education is the least with a average premium well below 1.3.
In sum, a BA/BS is not a guarantee of an 80% wage premium. Not all majors may be "worth it" economically, given the accounting costs and opportunity costs of getting the degree.
Trying to get a degree and failing can also be costly if multiple years are burned up in the attempt. Dropping out without a degree after 5 years of going to college is on average, an economic disaster.
Note that these graphs are equally consistent with both the signaling and capital formation views of higher ed.