More than one-fifth of workers over 40 in New York and across the U.S. have experienced age discrimination according to a recent survey by specialty insurer Hiscox USA. As a result of the findings, the company is warning companies to address the issue to avoid discrimination lawsuits.

For the survey, Hiscox researchers polled 400 full-time American workers age 40 and above. They found that 21% of participants said they have encountered age-related workplace discrimination. They also found that most participants began noticing discrimination around the age of 51. Despite experiencing age-related discrimination, only 40% of participants chose to file a charge or complaint. Of those who declined to report the discrimination, 54% said they didn’t want to create a hostile work environment as the reason for not taking action. Another 24% cited not knowing how to make a complaint as the reason.

According to the survey, men are more likely than women to report feeling that ageism harmed their career. Around 43% of male participants said they experienced more difficulty finding new jobs after turning 40. In comparison, 30% of women said they experienced the same problem. Meanwhile, 40% of male participants said that turning 40 slowed their career advancement. Around 24% of female participants reported the same. Hiscox says that companies can help prevent age-related discrimination by providing employee training and swiftly and effectively responding to discrimination claims.

Under state and federal law, companies are prohibited from discriminating against workers based on their age. Workers who believe they have been subjected to age-related workplace discrimination may turn to an attorney for advice. After reviewing the details of the case, the attorney may recommend filing a claim with the U.S. Equal Employment Opportunity Commission, which might lead to a settlement for lost wages and other damages.