As many as 10 percent of U.S. employees who miss work due toon-the-job stress may be absent from work for21 days or more a month. Almost another quarter may not show up onthe job due to stress for as many as 20 days a month.

This is among the highlights of Mind the Workplace, an in-depth survey ofthousands of U.S. workers across all industries by Mental HealthAmerica (formerly the National Mental Health Association). Thesurvey queried respondents on a wide range of factors related totheir work environments, and found that, despite the ongoingbullish economy, employers are doing little to improve morale at work.

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The absenteeism numbers were particularly disturbing. Althoughthe majority of respondents said they either never or rarely missedwork due to stress, fully a third reported that they stayed awayfrom work from two to 30 days each month because the environmentwas so stressful.

Of those who missed work due to stress, 35 percent said theymissed three to five days a month, and 38 percent said they missedsix days or more. A shocking 14 percent said they stayed away forbetween 21 and 30-plus days.

When asked whether work frustration or stress resulted in“unhealthy behaviors such as drinking or crying frequently,” thepercentages revealed a deeper level of unhappiness. Twice as manyrespondents said they sometimes, often or always engaged in suchbehaviors as respondents who said the rarely or never did so.

The price for permitting such a work environment is staggering.The association estimates that it costs employers $500 billion inlost productivity annually.

“It isn’t just the financial losses that matter,” said MentalHealth America President and CEO Paul Gionfriddo. “Overstressed andunhealthy employees contribute to unhappy workplaces. This meansthat the indirect effects on everyone else – the people who dreadcoming to work – may not show up in the calculated productivitylosses, but contribute to them nevertheless.”

The study was jam-packed with what Gionfriddo understatedlytermed “eye-opening results.” Among them:

• Two-thirds said they worked in an environment that was hostileor unhelpful

• Two-thirds said they didn’t often trust their coworkers tosupport them at work

• Two-thirds said their supervisor would not generally besupportive if they were having trouble at work

• More than eight in 10 said their employers didn't dealappropriately with slacking coworkers

• More than eight in 10 said the stress at work directly causedstress with family and friend relationships

• More than seven in 10 admitted they bad-mouth their employeroutside of work

Not surprisingly, the survey found that nearly three-quarters ofall employees are either actively seeking a new job or are thinkingabout doing so. And turnover is not only expensive but representsanother productivity killer.

According to the study, “Voluntary and involuntary turnoverrates have direct and indirect costs for companies. The cost ofreplacing one employee is estimated to be about 20 percent of theirsalary, but can increase to 50 percent for various positions.Organizations must invest in replacement costs such as vacancyadvertisement, screening applications, testing and interviewing,etc. Additionally, there are costs associated withorienting and training new employees.

“High turnover rates cause a decline in workplace productivity,as they demand a shift in the distribution of work while newhires are recruited and trained,” the study continued.

On a brighter, proven strategies exist for turning around lowengagement numbers and improving workplace environments to promotebetter attitudes among employees and relieve stress.

“Perceptions about one’s contribution to the workplace, and therecognition (or lack thereof ) they receive, has a huge impact ontheir level of engagement. Within every industry and organization,its leadership can begin to identify where the disconnect lies, andimplement practices and policies that may address them,” the studyconcluded.