$300 billion per year $300 billion dollars a year forty percent of American workers cost of stress costs cost of stress $300 billion $300 billion each year $300 billion costs Forbes August 2, 2012 $300 billion le cuesta a las empresas $300 billion 300 miliardi di dollari l'anno forty percent of American workers Stress hundreds of billions of dollars per year $300 billion forty percent of American workers Forbes August 2, 2012 businesses lose up to $300 billion a year