From this article on Redbox:
In 2005, Redboxes were in 600 locations and rented 24,000 movies a week. Today, they’re in more than 15,600 locations, renting 7.5 million movies weekly, Redbox says, not far below the 10 million-plus weekly rentals claimed by Netflix.
Netflix offers more than 100,000 unique titles. Each Redbox kiosk has slots for 600 discs, but the average number of titles is just 200, accommodating multiple copies of the most popular.