But the problem is Ian that, despite what they claim, very little of their calculation is genuionely based upon risk. The larger part of it is based upon the targets ability and likely willingness to pay.
An example, one of many. 9 years ago I moved house. I moved from one village to the neighbouring one, a distance of 1.1 miles. The move took me from one nice, affluent village to an even nicer, more affluent one.
I phone my insurers, Swindles, and informed them of the move. Unsurprisingly, my insurance premium went up. It's the additional risk, you see Sir.
Risk? Really?
I went to work and immediately pulled up the crime data for both locations. New location had a lower reported theft of motor vehicle, and a lower reported theft from motor vehicle, and a lower reported rate of criminal damage to motor vehicle.
I then checked the RTA (as it was then) stats for both post codes. Lo! The new postcode had a lower rate, unsurprisingly, as it had no main road running through it.
I rang the insurers back and asked them to explain the source of this increased "risk". I got the usual blather, until I pointed out that I was a copper and had access to all the crime statistics - I was actually less likely to have my car stolen, less likely to have my car damaged, less likely to be in a collision, and had the data to prove this, so where did the extra "risk" come from?
Lots of "er" and "ahh" and "uuummm", and my premium was recalculated. Funnily enough, it was lower than it had been at my original address.
The algorithms that calculate your premium take you genuine risk into relatively minor account - you job, and hence your likely income, your credit record, all sorts of other data actually completely irrelevant to the calculation of "risk" are taken into account. "Risk" is an excuse trotted out, and 2/3 of it is a bare faced outright lie, as I demonstrated it to be in my case.