The principal sources of employment law include common law, law of contract and the statutes. Presently, the Employment Rights Act of 1996 and the Trade Union and Labour Relations Act of 1992 are the prime statutes. The first discernable law in United Kingdom on labour matters was the Ordinance of Labourers, 1349 and it regulated the maintenance of wages at rates to be fixed from time to time by justices of the peace. The statute of Artificers 1562 also supported the maintenance of wages and prohibited conspiracies to raise wages. Initially, the Factory Acts, 1802 and 1833 and the Master and Servant Act, 1832 regulated the labour relations in United Kingdom. Before 1960, all the Employment laws were based upon law of Contract. These laws have witnessed significant expansion owing to the Equality Movement and the European Union. In the modern times, the most important Employment Law legislation was the Equal Pay Act of 1970 which came into effect in 1972. This Act aimed to effect equality for women in the workplace. However, average wage of women is still much below the equivalent standard wage for men. There have been major changes in the employment law of the United Kingdom since the Labour Government came into power in 1997. The maternity and paternity rights have been increased. A National Minimum Wage and the Working Time Directive has been introduced which regulates the working time, rest breaks and the right to paid annual leave. The law on discrimination has also been made stricter to provide protection against discrimination on the basis of age, religion or belief and sexual orientation as well as gender, race and disability. Since 1919, the United Kingdom has been a member of the International Labour Organisation and thus bound by the ILO Conventions it has ratified and which are in force.