NEW YORK — As it did in the morning two years ago, ABC News has broken a long-running winning streak by its rivals at NBC News.

ABC’s “World News” beat NBC’s “Nightly News” in viewership last week, only a month after David Muir took over as anchor from Diane Sawyer. NBC’s Brian Williams-led newscast had ruled for 263 consecutive weeks, a streak that began in September 2009, and for 310 of the past 311 weeks.

Last week ABC’s broadcast averaged 8.42 million viewers, while NBC had 8.25 million, the Nielsen company said.

In 2012, ABC’s “Good Morning America” broke an even longer winning streak in the morning by NBC’s “Today” show.

ABC has been creeping up in the evening ratings the past several months, often winning among the 25-to-54-year-old demographic that advertisers consider valuable.