From Cork Gaines of Business Insider:
In 1994, the NFL moved kickoffs from the 35-yard line back to the 30-yard line, and the result was a 32.3% increase in the average number of kickoffs per game. But in the era of concussion awareness, the NFL reversed that move prior to last season, moving the kickoffs back to the 35-yard line.
The move has led to a huge drop-off in the number of kickoff returns. From 1994 through 2010, the NFL averaged 8.2 kickoff returns per game. Since the start of the 2011 season, that number is now 5.4 returns per game, a drop of 34.1%, despite a large increase in scoring in recent years.
The result is that kickoffs have become nearly meaningless, and are now nothing more than an overly stylized way of transferring possession to the opponent. A ritual that is full of sound and fury, but signifying almost nothing...