The 2018-19 TV season ended in late May. On Sunday, it ends again.

As year-round programming has become the norm for broadcast networks, 52-week, September-to-September ratings have become a battleground for bragging rights — to the point that NBC and CBS each asserted claims to No. 1 status a year ago.

As the full 2018-19 year closes, there's no such tiff: While the numbers have changed some since May, the top of the rankings has not. With a few days left before the Nielsen-sanctioned start of the 2019-20 season, NBC remains first in the key ad-sales demographic of adults 18-49, and CBS is No. 1 among total viewers. Nothing airing in primetime before Sunday's final day of the season is liable to change that.

Below is a rundown of where the broadcast networks stand after the past 51 weeks.

The Big Picture

Collectively, the audience for the five English-language broadcast networks declined by 7 percent in the past year: From Sept. 24, 2018, through Sept. 15, 2019, they've averaged a combined 24.67 million viewers, down from 26.64 million a year ago. The adults 18-49 demographic fell a bit more, slipping by 11.5 percent year to year (5.4 rating vs. 6.1 in 2017-18).

Some of that decline is attributable to it being an odd-numbered year, which means no Olympics. NBC, which last season had both the Super Bowl and 18 days of Winter Olympics broadcasts, suffered the steepest declines among the Big Four nets in both viewers (17 percent, 7.81 million to 6.45 million) and adults 18-49 (22 percent, 1.8 to 1.4).

Adding Spanish-language broadcasters Telemundo and Univision to the totals, the total-viewer decline remains at 7 percent. The 18-49 loss increases a bit to 13 percent (6.2 vs. 7.1 a year ago), as both networks lost a bit of their under-50 audience year to year.

Fox, with big assists from Thursday Night Football and The Masked Singer, is the only network to increase its total audience. It grew by 7.5 percent to 4.46 million viewers, while remaining flat in adults 18-49 at 1.2. ABC and CBS each took single-digit declines in both the 18-49 demo and viewers.

As was the case in the September-to-May season, NBC will finish first over the past 52 weeks in adults 18-49, where its 1.4 rating is 0.2 ahead of ABC, CBS and Fox. CBS has held its total-viewer lead through the summer, and its 51-week average of 7.4 million viewers is almost a million clear of second-place NBC.

The CW, which doesn't put as much stock in linear ratings as its counterparts, nonetheless took some losses, falling from 1.51 million viewers a year ago to 1.17 million and dropping a tenth of a point in both adults 18-49 (0.5 to 0.4) and its core constituency of adults 18-34 (0.4 to 0.3).

All those figures, incidentally, are "most current" in Nielsen parlance — a combination of live-plus-7 ratings for most of the season and same-day numbers for the most recent weeks, for which delayed-viewing figures aren't yet available. They don't measure viewing on other platforms or beyond one week after a show's initial airing but that are becoming a larger slice of the broadcast pie. Fox, for example, says its multiplatform audience for 2018-19 to date is 7.4 million viewers — almost 3 million more than the Nielsen measure.

Univision vs. Telemundo

Univision retained its lead over Telemundo, although the gap has narrowed. The two Spanish-language networks are separated by 130,000 total viewers (1.32 million for Univision, 1.19 million for Telemundo) and in a near dead heat in the 18-49 demo: Both are at 0.4 ratings, with Univision averaging 550,000 viewers in that age group to 540,000 for Telemundo.

Telemundo is touting a victory on weeknights, outdrawing Univision from Monday to Friday in adults 18-49 and 18-34. Univision has a stronger weekend lineup, including sports, that keeps it in front for the overall Spanish-speaking lead.

Summer Leaders

NBC is poised to lead its fifth consecutive summer season in viewers, paced by a declining but still strong America's Got Talent. It has some company, however, atop the 18-49 rankings.

With strong runs from The Bachelorette — the top series of the summer in adults 18-49 with a 2.1 rating — and Bachelor in Paradise and a bigger footprint of originals across the week, ABC is currently tied with NBC in the 18-49 demo. Each network is averaging a 1.0; ABC is even with its performance in summer 2018, while NBC has come down by a couple tenths of a point.

Other Dayparts

Stephen Colbert held onto his late-night lead during the summer, with CBS' The Late Show maintaining a slim margin over NBC's The Tonight Show Starring Jimmy Fallon in adults 18-49 (0.49 to 0.48) and a sizable cushion in total viewers (3.63 million to 2.31 million). ABC's Jimmy Kimmel Live! is at 0.38 in the 18-49 demographic and just under 2 million viewers.

In daytime, well, even in the ever-changing TV landscape some things remain the same. CBS is wrapping up its 33rd straight year as the leader in daytime, a streak that began during the Reagan administration.

Facts and Figures

– High-income people apparently love the Bachelor franchise. The two weekly installments of Bachelor in Paradise, The Bachelorette and The Bachelor are the top four broadcast series of 2018-19 in terms of median viewer income among viewers ages 18-49. Monday's Bachelor in Paradise sits on top; its audience has a median annual income of $97,500.

– Since the end of the traditional broadcast season in May, The Masked Singer has added about 200,000 viewers to its season average and is up to 15.9 million multiplatform viewers. The Jan. 2 series premiere is at 20.3 million viewers (up from 20 million in May), including 5.5 million on Hulu and Fox Now. The latter figure makes it the network's most-streamed episode ever.

America's Got Talent has been on the air for 14 seasons, and it has been the most-watched summer series in every one of those seasons. This season, the Tuesday edition averages 10.7 million viewers with three days of delayed viewing, and the long-tail five-week average (across all platforms) is 17.8 million.

– The broadcast networks aired 55 original entertainment series in the summer (including a handful that continued in-season runs), up from 42 in 2018. Since the start of the 2018-19 season, they've aired 177 series, not including sports and news programs.

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