Jaffray's report on the state of teens in the U.S. suggests that Facebook is still the most important social network among teens, but usage has declined by nine percent since last year.
BusinessWeek points out that Facebook's popularity among this "fickle demographic" has dropped significantly since the same time last year. Decline in usage could be attributed to, "so many parents and grannies that seem, creepily, to be all over Facebook these days," BusinessWeek says .
Here's the chart included in Piper Jaffray's report:
More From Business Insider