PokerStars is increasingly using the popular Progressive Knockout format to keep attendance high of its iconic Sunday Million tournament under its new half-priced buy-in format, data collated by PRO reveals.

The Sunday Million, online poker’s longest and most prestigious weekly tournament, was changed from a $215 buy-in to a new $109 format in late January. It kept the $1 million guarantee the same, meaning it needed to attract 10,000 players every week in order to cover the guarantee.

The switch was ambitious, and it was not without its problems. While the first week was successful—it attracted over 15,000 entries—numbers dwindled over the next few months. By March and April, it was only just scraping over 10,000 entries.

On June 2, it saw its first ever overlay—only 8984 players subscribed to play, resulting in a significant $101,600 overlay.

But since then, numbers have been rebuilding. There has been no overlay repeat and, since the June low, numbers have been growing. Throughout July and August, attendance grew by a couple of hundred entries each week. In the last few months there have been some noticeable spikes, with a record high set in mid-August and another top turnout last Sunday, with almost 14,500 entries.

However, PokerStars did not leave this to chance.