A sharp decline in TV shooting pushed down offlot activity in Los Angeles by 21% for the week, with 510 permitted production days during the week that ended Sunday, compared with the year-ago period.

The weekly decline was the largest this year, according to figures released Tuesday by the FilmL.A. permitting agency.

Smallscreen shoots logged 326 days — 110 fewer days than the same week in 2010. The slide was led by a decline in TV dramas, from 109 days to 67 days — even though the number of permits was nearly identical. “That means companies are (requesting) fewer locations (per permit) and spending fewer days per location,” noted FilmL.A. spokesman Todd Lindgren.

NBCUniversal was the most active offlot TV producer, with 30 days during the week, led by 20 days for “The Office.” Other TV projects shot currently include “Master Chef 2,” “Common Law,” “Parenthood,” “The Glee Project,” “True Blood,” “Private Practice,” “CSI” and “Brothers and Sisters.”

Feature activity edged down by two days to 52 days. The most active feature production during the period was DreamWorks’ “Welcome to People” with eight days.

Other features shooting offlot in Los Angeles include “J. Edgar,” “We Bought a Zoo,” “Default” and “X-Men: First Class.”

Commercials posted a 15% decline during the week, with 132 days.

Radical Media was the most active producer, with 12 dates for a Bing spot.