A large number of crimes are not reported because of public tolerance to certain types of crime and to the increasing rate of crime.
The British Crime Survey estimated a total of 15 million crimes in England and Wales in 1991, two-thirds of which were unreported. It suggests that while 99% of car theft and 92% of burglaries (where loss is suffered) are reported to police, only 50% or fewer of many other offences (robbery, woundings, thefts) are reported. More crimes are being reported than when the survey began in 1982, largely because of wider insurance.