The majority of general practitioners are independent contractors and do not receive salaries as such. Instead, they take a share of the net profit their practice makes in a year, after taking into account all earnings and expenses of the practice. The new contract determines a significant proportion of the earnings a practice receives. In agreeing the new contract, the Government guaranteed to increase investment in primary medical care services by 36 per cent. or £1.8 billion, in England, over three years ending 2005-06.