2013 hasn't been especially kind to Facebook. The Facebook Home app launcher, announced in April, was poorly received by consumers. Then, in June, the social media service fell under the scrutiny of privacy advocates as information surfaced about Silicon Valley's relationship with the NSA.
But perhaps most damning of all, research suggested that Facebook might not be the super-fun, up-with-people service that Zuck and company envisioned.
In January, a study published by Berlin's Humboldt University reported that Facebook makes us envious. In August, a University of Michigan study told us that Facebook makes many young people depressed.
Have you had similar reactions? Compare your own Facebook experience to the sample index below, and ask yourself if Facebook is, on balance, a good thing or a bad habit.