Also, the insurance companies don't increase prices proportionally for males according to the statistics. he British Insurance Brokers' Association (BIBA) said currently the cost of the average car claim by an 18-year old man was £4,400, while that for an 18-year old woman was £2,700. (
http://www.bbc.co.uk/news/business-12606610)
So on average, Men cost insurance companies 1.6 times more than women do. Yet my insurance is £3,000. A friend of mine pays £900. We have the exact same car, we live in the same area (half a mile apart), same age. The difference? She's female.