While employers promote 8.9% of their employees annually, some 3.2% of employees leave an organization each month, according to an ADP Research Institute report released on Tuesday. Based on the payroll data of more than 13 million employees, the report reveals trends in businesses’ hierarchy, turnover, promotions, and more.

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Promotions within an organization are also associated with higher ultimate turnover among other team members, the report found. Those who didn’t receive a promotion often feel as though they have been overlooked or are undervalued.

“While promotional opportunity may be perceived as a net positive, it can also have negative impact for team members who have been passed over,” Ahu Yildirmaz, co-head of the ADP Research Institute, said in a press release.

Organizations are much more likely to promote internal employees for management positions, and the probability of promotion exceeds 20% for those who have reached higher levels of management in the company, the report added. Companies promote internally to management 17% of the time, while new hires make management 15% of the time.

Employees who have managers with more direct reports are more likely to leave the company, the report found. Direct reports’ turnover for managers with four to six employees is 2.3%, but the turnover for managers with more than 15 direct reports is 3.5%.

For advice on how to retain employees, regardless of promotion, check out this TechRepublic article.