Similar to Supergirl and The Flash, the Invasion crossover episode for Arrow gave the series high ratings. Here's the official info via The CW:
ARROW SHOOTS TO SEASON HIGHS
The 100th Episode of “Arrow” is the Series’ Most Watched and Highest-Rated Episode Since Last Season’s Crossover Event
December 1, 2016 (Burbank, CA) ─ The 100th episode of ARROW hit its mark, delivering the series’ most watched (3.52M) and highest-rated episode since last season’s crossover episode (12/2/15), according to preliminary fast affiliate ratings from Nielsen Media Research for November 30, 2016.
ARROW more than doubled its rating in adults 18-34 (1.1/5) from last week, +120% from its last original episode, and matching last season’s crossover rating.
ARROW drew a 1.3/5 in adults 18-49, +86% from its last original episode and off only a tenth from the crossover last season.
ARROW tied for #1 in the hour in adults 18-34, and was #1 in men 18-34 (1.3/6), and tied for #2 in men 18-49 (1.5/6).
This was The CW’s most watched Wednesday night (2.3M) since 1/27/16, and its highest rated Wednesday in adults 18-34 (0.7/3) since 2/24/16, and since 5/25/16 in adults 18-49 (0.8/3).
This season, ARROW is averaging gains of +77% in adults 18-49, +69% in adults 18-34, and +61% in total viewers in Live + 7 Day delayed viewing over its Live + Same Day totals alone.
