A rating of the employees’ health could legitimately be part of a company's balance sheet. It fits in well with the philosophy of sustainability. Obesity and tobacco usage has been also shown to impact productivity. Knowing that one company has a healthier workforce than its competitors could be a competitive advantage. Investors may also benefit from knowing about the mental health and well-being of a firm’s employees. Occupational health psychologists will point out that stress free employees are less likely to make errors in certain jobs. Does the employer have the right to track the data related to employees' health and wellness?