As it heads toward the conclusion of its 12th season, "Big Brother" is having a strong summer in the ratings.

The Nielsen Co. said Tuesday that the CBS reality show is averaging 7.6 million viewers for its three weekly episodes. That’s up 6 percent from last year. Among adults 34 and younger, ratings are up 10 percent.

Executive producer Allison Grodner says one of the reasons the show is doing well is because of a likeable cast. That’s a lesson the production staff learned last year _ that it’s possible to have villains that people don’t necessarily hate.

The show is working toward its season finale on Sept. 15.