From a report by Josh Bivens and Larry Mishel that I linked to in last week’s Digest (but have only skimmed to date).  Paul Krugman posted a nice top-level takeway yesterday evening.  From his concluding paragraph:

…the next time you hear someone claiming that middle-class families have, in fact, seen a big rise in living standards, you should know that to the extent that this is true (which is less than claimed), it’s mainly about working more hours. Pay really has almost stagnated despite rising productivity.