NEW YORK Almost one-quarter of all U.S. television households (23.3 percent) own a high-definition TV set as of Nov. 30, Nielsen  reported Thursday.
Nielsen's estimates are based on a field staff review that identified TV sets capable of receiving and displaying high-definition pictures, as well as those that are actually receiving those signals.
High-definition TV penetration in the U.S. has more than doubled since July 2007, when Nielsen began tracking HDTV status. At that time, only 10 percent of U.S. homes had access to high-definition TV.
Washington, D.C., where 31 percent of homes are HDTV-enabled, has the highest HDTV penetration of Nielsen's 18 largest local TV markets. Boston and New York follow, with HDTV penetrations of slightly more than 30 percent, respectively. Detroit has the lowest HDTV penetration: about 21 percent of homes.
Sporting events have the highest index of viewing in HDTV households, with HDTV receivable and capable homes watching 54 percent more sports than households that are not HDTV capable. Political programming and awards shows are also popular with HDTV households.
Adweek is a unit of the Nielsen Co.