While most shows saw a ratings decrease on Wednesday night, Arrow was one of the few shows that showed a ratings increase. Arrow's ratings rise was likely driven by a guest appearance by Matt Ryan reprising his role as Constantine from the canceled NBC series.
Arrow scored a 1.0 rating in key demographics and 2.57 million viewers. This was a 10% increase over the previous week, which saw a 0.9 rating for Arrow. The 1.0 rating is just short of the season 4 premiere rating of 1.1, which had been the highest ratings since the series premiere.
In general, it seems Season 4 of Arrow is being well-received by fans, so ratings are looking strong for the fourth season. It should also be noted that the Constantine episode was able to drive a ratings increase, despite being leaked early online.