All data obtained from @SonOfTheBronx on Twitter:
Son Of The Bronx/Programming Insider

Dec 23rd, 2017 (Cowboy Bebop Marathon)

Time
Show
Ratings
A18-49
10:30am Cowboy Bebop 661,000 394,000
11:00am 510,000 360,000
11:30am 526,000 310,000
12:00am 496,000 360,000
12:30am 419,000  233,000
1:00am 370,000 216,000
1:30am 354,000  210,000
2:00am 314,000  195,000
2:30am 308,000 191,000
3:00am 355,000 200,000
3:00am 361,000 202,000


comparison

Dec 24th, 2016 (Scavengers/Jojo Marathon)

Time
Show
Ratings
A18-49
12:00am Scavengers 1,107,000 718,000
12:15am Jojo’s Bizarre Adventure 811,000 519,000
12:45am 676,000 428,000
1:15am 546,000 365,000
1:45am 497,000 344,000
2:15am 460,000 326,000
2:45am 408,000 294,000
2:15am  Scavengers 413,000 268,000

If you want more data, you can check my spreadsheet here. That will have further data including per year difference and A18-49 differences.

Let us know what you think in the comments below about the ratings.