NBC’s Brian Williams celebrated his third straight week — and fifth week of the most recent seven —  as top-rated evening anchor in the news demo. The week of December 15-19 also marked NBC Nightly News’ 275th consecutive week at No. 1 in overall audience, with its biggest total viewer advantage in fourth months over ABC. Williams’ newscast is posting its best start to a season in nine years, widening its lead by 24% week-to-week.

NBC News had kicked off the week announcing Williams, who this month celebrated the 10th anniversary of assuming the evening news chair with a slow jam of the news on NBC’s Tonight Show, had “renewed his commitment” to the news division for “years to come.”

Though ABC World News Tonight With David Muir had last week featured Muir’s exclusive with President Obama on the United States’ historic move with Cuba, and exclusive video of Ray Rice and now-wife Janay after he clocked her in that casino elevator, Williams snagged an average 9.360 million total viewers for the week to beat ABC’s newscast by 10% (840,000), also besting CBS Evening News With Scott Pelley, by 28% (2.027 million). It’s Williams’ biggest total viewer advantage over ABC in four months. In total viewers, Williams now has outperformed ABC by at least 500,000 viewers and CBS by at at least 2 million viewers for an 8th straight week. (Williams’ broadcast is averaging slightly more than 9 million viewers this TV season, which NBC notes is its biggest audience for the start of a season in nine years, putting it on top of the evening news ratings derby in total viewers for 273 consecutive weeks. Unlike 9 years ago, that number outstrips much of NBC’s primetime slate.)

Nightly averaged 2.150 million news demo viewers for the week  – 2% (34,000) ahead of ABC and 29% (478,000) more than CBS. Williams also averaged 1.606 million viewers in the 18-49 demo -– topping ABC by 12% (176,000) and CBS by 45% (500,000).

All that said, ABC World News Tonight stands as the No. 1 evening newscast in the news demo, season to date, with a 12,000 viewer advantage over NBC. This marks the first time in 7 years the ABC newscast ranks as the top evening newscast in the news demo during the season. ABC World News Tonight also has slashed its season gaps with NBC by 41% in total viewers (617,000 vs. 1.038 million) and by 58% in the younger age bracket (121,000 vs. 287,000) to its closest performances in six years and seven years, respectively.