United States labor law sets the rights and duties for employees, labor unions, and employers in the United States. Labor law's basic aim is to remedy the "inequality of bargaining power" between employees and employers, especially employers "organized in the corporate or other forms of ownership association". Over the 20th century, federal law created a series of minimum social and economic rights, and encouraged state laws to go beyond the minimum to favor employees. The Fair Labor Standards Act of 1938 requires a federal minimum wage, currently $7.25 but higher in 28 states, and discourages unhealthy working weeks over 40 hours through time-and-a-half overtime pay. Unlike every other democratic country, there are no federal or state laws requiring paid holidays or paid family leave: the Family and Medical Leave Act of 1993 creates a limited right to 12 weeks of unpaid leave in larger employers. There is no automatic right to an occupational pension beyond federally guaranteed social security, but the Employee Retirement Income Security Act of 1974 requires standards of prudent management and good governance if employers agree to provide pensions, health plans or other benefits. The Occupational Safety and Health Act of 1970 requires employees have a safe system of work. A contract of employment can always improve standards beyond the minimum statutory rights. To get fair terms beyond the statutory minimum, and improve upon individual contracts, employees must organize a labor union for collective bargaining. The National Labor Relations Act of 1935 creates rights for most employees to organize a labor union, without any detriment through unfair labor practices. Under the Labor Management Reporting and Disclosure Act of 1959, labor union governance follows democratic principles. In any workplace where a majority of employees support a union, employing entities have a duty to bargain in good faith. Unions can take collective action to defend their interests, including withdrawing their labor on strike. There are not yet general rights to directly participate in enterprise governance, but many employees and unions have experimented with securing representation on corporate boards.