Budd, Sharp, and Mayhew (2005) identified this pattern through a UK-based survey, which identified that 2% of the self-reported offender sample were responsible for 82% of all reported offences.
One reason is that 96% of reported offences stay unsolved.
They call it "cuffing", because the reported offences disappear up the officer's sleeve.
West Midlands Police, the second largest force, holds 1.1 million records of people who have reported offences during the past 12 years.
There were increases in reported offences for all five of the monitored hate crime strands between 2013-14 and 2014-15.
In the case of Savile, there were five reported offences, from 1979 to 1988, which ranged from sexual assault to rape.
The number of reported offences continued to decline in the following years as the popularity of the programme waned and its eponymous star grew steadily older.
"However, it is not easy to evidence this from the existing published data because reported offences continue to be presented in such a way that they reflect the age at the time the offence took place, but not at reporting.
Cooper's speech in Birmingham will also highlight the drop in prosecutions and convictions for rape, child sex offences and domestic violence even though reported offences are going up.
The number of reported offences against him peaked in 1976 at 15 - a time when 350,000 predominantly young people were writing to him each year to ask him to make their wish come true.
