ABC's World News with Charles Gibson was back on top of the evening news ratings last week, taking first place in both Total Viewers and the A25-54 demo for the first time since April 7. The 210,000 Total Viewer victory was the largest advantage by ABC over second-place NBC since the week of October 29.

Week-to-week, ABC was the only network to gain in Total Viewers, while all three networks saw slight decreases in the demo.

Total Viewers: ABC: 8,010,000 / NBC: 7,800,000 / CBS: 5,620,000

25-54 demo: ABC: 2,380,000 / NBC: 2,280,000 / CBS: 1,780,000

25-54 rating: ABC: 1.9/8 / NBC: 1.8/8 / CBS: 1.4/6

All three network evening newscasts were up last week, with third-place CBS Evening News gaining +430,000 Total Viewers week-to-week (the week of April 21 was EN's lowest-rated week on record). NBC Nightly News with Brian Williams wins the week in Total Viewers and the A25-54 demo.

Total Viewers: NBC: 8,180,000 / ABC: 7,960,000 / CBS: 5,770,000

25-54 demo: NBC: 2,540,000 / ABC: 2,390,000 / CBS: 1,790,000

25-54 rating: NBC: 2.1/9 / ABC: 1.9/8 / CBS: 1.4/6

NBC Nightly News wins the week in Total Viewers while Nightly and ABC's World News tie in the demo. ABC was up in Total Viewers week-to-week, while NBC and CBS were down. Ditto for the demo, ABC up, NBC and CBS down. The CBS Evening News lost 50,000 viewers from the week prior, setting a new all-time low for the broadcast.

Total Viewers: NBC: 8,010,000 / ABC: 7,790,000 / CBS: 5,340,000

25-54 demo: NBC: 2,330,000 / ABC: 2,330,000 / CBS: 1,580,000

25-54 rating: NBC: 1.9/8 / ABC: 1.9/8 / CBS: 1.3/5

Developing: TVNewser has learned the CBS Evening News set another record low last week. The broadcast averaged 5.34 million Total Viewers and 1.58 in A25-54. The week prior, the broadcast drew 5.39M Total Viewers and 1.69M in A25-54.

We'll have a clearer picture later this morning about whether the other network broadcasts gained or lost viewers week-to-week.

• Related: Time's James Poniewozik calls for Couric's replacement to not just be another, "white guy."

The recent news about Katie Couric's supposed departure from the CBS Evening News anchor chair seems to resonating with those who matter most: her viewers. Last week, the Evening News posted its lowest ratings since Couric's Sept. 2006 debut; in fact they are the lowest numbers since Nielsen began tracking the ratings during the 1987-88 season. The broadcast lost 170,000 viewers week-to-week, setting a low not seen since since the week of Sept. 3, 2007.

NBC was up in Total Viewers and the A25-54 demo, week to week. ABC was down in both. NBC Nightly News wins the week in both categories.

Total Viewers: NBC: 8,170,000 / ABC: 7,510,000 / CBS: 5,390,000

25-54 demo: NBC: 2,390,000 / ABC: 2,220,000 / CBS: 1,690,000

25-54 rating: NBC: 1.9/8 / ABC: 1.8/8 / CBS: 1.4/6

ABC's World News with Charles Gibson took back first place again last week in the A25-54 demo and in Total Viewers, one week after Nightly News placed first in both categories.

Week-to-week, ABC was the only network to show gains in Total Viewers. All three networks saw decreases in the demo.

Last week's World News featured the first installment of "21 and the World is Yours."

Total Viewers: ABC: 8,030,000 / NBC: 7,920,000 / CBS: 5,560,000

25-54 demo: ABC: 2,520,000 / NBC: 2,360,000 / CBS: 1,760,000

25-54 rating: ABC: 2.0/8 / NBC: 1.9/8 / CBS: 1.4/6

NBC's Nightly News with Brian Williams was the ratings victor last week, in a reversal from ABC's World News the week before. Although NBC won the Total Viewers category by a solid margin, the A25-54 demo victory was by less than 10,000 viewers.

Week-to-week, all three networks saw significant drops in Total Viewers, while NBC saw a slight gain in the demo. The Total Viewers average was the lowest for the three networks since October 2007.

Total Viewers: NBC: 8,267,000 / ABC: 7,980,000 / CBS: 5,943,000

25-54 demo: NBC: 2,550,000 / ABC: 2,540,000 / CBS: 1,890,000

25-54 rating: NBC: 2.1/8 / ABC: 2.1/8 / CBS: 1.5/6

It was a victory for ABC's World News, as the broadcast finished first place in the A25-54 demo, and tied NBC's Nightly News for first place in Total Viewers last week. For the 2008 calendar year, ABC has won the demo six weeks while NBC has won it five weeks as well (one week the networks tied). In Total Viewers, NBC has won nine weeks compared to two for ABC (with this week counting as a tie).

For the first quarter (12/31/07-3/30/08), NBC took first place in Total Viewers by 310,000 while ABC slightly edged NBC in the A25-54 demo by 10,000.

Week-to-week, ABC and NBC fell in Total Viewers while CBS' Evening News saw gains. In the demo, all three networks lost viewers week-to-week.

Total Viewers: NBC: 8,410,000 / ABC: 8,410,000 / CBS: 6,630,000

25-54 demo: ABC:2,550,000 / NBC: 2,460,000 / CBS: 2,030,000

25-54 rating: ABC: 2.1/8 / NBC: 2.0/8 / CBS: 1.6/6

Just as the week before, ABC's World News and NBC's Nightly News split the ratings win last week. World News won the A25-54 demo and Nightly News won in Total Viewers. For the 2008 calender year, the tightest battle comes in the demo, where ABC has seen wins in five weeks while NBC has won it five weeks as well (one week the networks tied). In Total Viewers, NBC has won nine weeks compared to two for ABC.

All three networks saw big gains week-to-week, coming after a low week (due to the Daylight Saving Time switch).

Total Viewers: NBC: 8,920,000 / ABC: 8,460,000 / CBS: 6,620,000

25-54 demo: ABC: 2,650,000 / NBC: 2,570,000 / CBS: 2,220,000

25-54 rating: ABC: 2.2/9 / NBC: 2.1/8 / CBS: 1.8/7

It was a split decision last week for evening news ratings supremacy, as ABC's World News won the A25-54 demo and NBC Nightly News won in Total Viewers. Both network's newscasts were led by fill-in anchors, as Ann Curry held the Total Viewer lead all week on NBC, while losing the demo to the combination of Elizabeth Vargas and George Stephanopoulos.

All three networks saw significant drops in both categories week-to-week.

Total Viewers: NBC: 8,320,000 / ABC: 8,100,000 / CBS: 6,300,000

25-54 demo: ABC: 2,510,000 / NBC: 2,450,000 / CBS: 1,990,000

25-54 rating: ABC: 2.0/8 / NBC: 2.0/8 / CBS: 1.6/6