19 of the 20 Premier League clubs use Prozone

"Today, 19 of the 20 Premier League teams use Prozone. Each has its own team of performance analysts and data scientists looking for the indicators that quantify player performance, the events that determine matches and trends that characterise seasons. They are scientists dissecting the world's most popular game, looking at data from Prozone and other sources to understand what dictates the difference between winning and losing. In the environment of the multimillion-pound Premier League, clubs don't just want a competitive advantage, they need it."

Source:  Wired, 10th Januiary 2014