I recently started at a private company that does profit sharing through ESOP. This year to all invested employees, so those more than ~1yr, they contributed around 30% of their annual salary in stock to their retirement. The private stock price rose about 32% from last year as well. On average the stock goes up 20%+ and the contributions have been around 18%. The founder and IG CEO found that companies that have an ESOP grow faster than others, and are happier. It takes 6 years for full investment, but after that, when you leave, they pay out your shares at that stock price, over a few payments I believe.