Cinco de Mayo took its toll on TV last night, but CBS nonetheless celebrated a win in both the demo and total viewers. The revelries took a tenth out of primetime ratings, here and there, as viewers opted for partying over Live+Same Day viewing.

CBS’ The Big Bang Theory ratings magnet was the night’s top show in the two metrics, but clocked a season low at 8 PM — a 2.9 rating, 12.9 million viewers, eclipsing the previous season low of 3.1/13.5M.

Across primetime, some programs took smaller hits but others held steady, week to week.

ABC’s Grey’s Anatomy took over the demo lead at 8:30 (1.9, 7.5M), though CBS’ The Odd Couple prevailed in overall audience (1.6, 8.2M). ABC hopes Grey’s previous week Live+3 demo jump of 70% (its biggest-ever percent spike) might be repeated this week as viewers catch up on viewing.

CBS’ Mom (1.6, 8.1M) and 2 Broke Girls (1.6, 6.7M) dominated the 9 PM hour. At 10, CBS’ Rush Hour (0.9, 4.6M) and ABC’s The Catch (0.9, 4.4M) tied in the demo.

Fox’s Bones snagged a week-to-week improvement (0.9, 4.2M) but finished third in the 8 PM hour in Live+SD viewing. After that, Fox fell to fourth at 9 with American Grit (0.6, 1.9M).

The Blacklist (1.2, 6.5M) marked the high point of NBC’s primetime; staying steady week to week, it ranked third in the demo at 9, but second in overall audience, behind CBS’ comedies. At 8 PM, NBC’s  Strong (0.6, 2.6M) was a distant fourth in both metrics after taking a Cinco de Mayo-fueled one-tenth tumble. But, at 10 PM, Game Of Silence (0.7, 3.4M) came in third, though its was also one of the night’s few revelry-proof performers, climbing a tenth from previous week.

CW’s DC’s Legends Of Tomorrow (0.6, 1.6M) joined the Down A Tenth Club last night, though it matched NBC’s Strong in the demo. At 9 PM, The 100 held up week to week (0.4, 1.1M).