• by Wayne Friedman , December 16, 2013

An increasing number of top TV network shows -- 23 -- are now getting more key viewers from time-shifting than from live airings.

This compares to just 11 shows a year ago. The research comes from a 10-week analysis of the TV network season by Brad Adgate, senior vice president and director of research of Horizon Media.

A majority of these shows -- 15 of 23 -- are dramas. Only one is a reality show, CBS’ “Survivor." Four of those shows -- “The Office,” “Private Practice,” “Fringe” and “30 Rock” -- are not airing this season.

The highest time-shifting viewership of a TV show goes to one of the top-rated TV network shows overall: CBS’ “Big Bang Theory.” “Bang” gets a 3.8 average rating from 18-49 viewers through 10 weeks when it comes to time-shifting. Look at its “live only” rating, “Bang” registers a 3.36 number since the beginning of the season.

In second place is ABC’s “Modern Family,” with a 2.91 rating for all its time-shifted viewing and a 2.51 rating from its “live only” viewing. ABC’s “Grey’s Anatomy” comes next with 2.74 from time-shifting and 1.97 from live-only. NBC’s “The Blacklist” is averaging a 2.63 from time-shifting and 2.53 from its live viewing.

CBS’ “How I Met Your Mother” earned a 2.43 18-49 rating from time-shifted viewing and a 1.92 for “live only.” ABC’s “Marvel Agents of S.H.I.E.L.D.” tallied a 2.42 for its time-shifted rating and a 1.92 live-only rating. Fox’s “Sleepy Hollow” was at a 2.20 for time-shifting and 1.88 for live-only.

ABC, CBS and NBC have six shows with more time-shifting among adult 18-49 viewers than from their live-only airings; Fox had five.

Current Nielsen data shows that 49% of U.S. homes have at least one DVR .