'The Walking Dead' just hit its lowest ratings for a midseason finale in years

"The Walking Dead" is still one of the most-watched shows on television, but it's becoming harder and harder for the zombie series to compete with its own past ratings.

Sunday's season-seven winter finale attracted 10.6 million total viewers, according to Deadline.

By the way, that's still a great number for television - broadcast or cable. But it ranks as the show's lowest-watched midseason finale in four years, since season three in December 2012. It's also 24% lower than last year's winter finale episode.

As for the all-important under-50 audience for advertisers, Sunday's episode earned a 5.1 rating. That's a 27% drop from last year's winter finale. The good news is that's it's a 4% improvement over last week.

Sunday's finale ratings also follow a series of lows for the season, so it's not a good pattern for "The Walking Dead."

It should be pointed out that Sunday Night Football has competed against "The Walking Dead" several times, though it wasn't a factor this past weekend. Also, the show tends to pick up a lot of views in delayed viewing. The December 4 episode increased by 42% in live-plus-three-day viewing numbers, Deadline pointed out.

Season seven continues on February 12.