It's no secret that an employee's manager has a very direct impact on their happiness at work. Great bosses tend to have happier employees than bad bosses do. Today, job site LinkedIn revealed the results of its research into exactly what bosses do that make their employees happy and want to stay.

After reviewing a total of 32 million LinkedIn profiles, LinkedIn found that, after 12 months at a company, there's a 76 percent chance of an employee still being there. After two years, this number drops to just a 59 percent chance that the employee will still be there. And after three years? Only a 48 percent chance.

LinkedIn took a closer look at its data to figure out why this is the case. Researchers found that great bosses do 3 very specific things to make their employees happy. And happy employees tend to stick around. Here's what LinkedIn discovered in its research:

1. Employees who change positions internally stay way longer--even if they're not getting a promotion.

LinkedIn found that, after three years, someone who was promoted is 70 percent likely to be there, while someone who moved laterally has a 65 percent chance. In comparison, someone who is stuck in their same position--with no promotion and no lateral move--has only a 45 percent chance of still being at that company after three years. Great managers provide employees with opportunities to change positions internally--either as a promotion or a lateral move to a new function. According to LinkedIn's findings, their employees are happier and are much, much more likely to stick around than those who stay in the same role.

2. Great management matters: Companies with highly rated management saw better retention. 

LinkedIn's research also revealed that companies rated highly for "open and effective management" experienced significantly greater retention. After three years, there was a 48 percent chance of employees still being at those companies. For businesses with low management scores, however, there was just a 32 percent chance of an employee lasting three years. One 2017 survey found that 56 percent of employees would turn down a 10 percent pay raise to stay with a great boss. As the old saying goes, people don't quit their jobs, they quit their managers.

3. Empowered employees are loyal employees.

When LinkedIn cross-referenced its employee value propositions survey (things like "good work-life balance" or " a purposeful mission") with its retention data, it discovered that companies perceived to be places where "employees have influence"--who are empowered--had workers that tended to stick around longer. In fact, after three years, there's a 47 percent chance of an employee sticking with them. Compare this to companies that are seen as less-empowering, where employees have only a 35 percent of being there after three years. So, if you're a manager, be sure to empower your people by giving them the authority they need to get their jobs done.