The 1,000-page study, obtained by The Sunday Times, will be launched this week by Britain's anti-terrorism chief and Scotland Yard Assistant Commissioner Mark Rowley.
It also disclosed that women's involvement in Islamist- inspired terrorism has increased three times over the same period.
Stabbings or threats to behead have also increased, from just four incidents in 1998-2010 to 12 since, and now form almost half of attack-related convictions.
The study also raises concerns of segregation within Britain's Muslim communities as a tenth of all Islamist terrorists come from just five areas in Birmingham.
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"This study identifies some significant new challenges for the authorities, including keeping track of a new generation of terrorists. I hope it will also tackle some of the myths that are prevalent in this area," The author of the report, Hannah Stuart of the Henry Jackson Society, told the newspaper.
Among her findings is the revelation of some geographical clusters of terrorism in the UK which do not necessarily correlate simply to areas with a high Muslim population.
Birmingham, with 234,000 Muslims, has a total of 39 convicted terrorists.
Just five of Britain's 9,500 council wards - all in Birmingham - account for 26 terrorists, a tenth of the national total.
The study also dismisses claims that attacks are committed by "lone wolves" as only 28 of the 269 acted alone. Almost 80 per cent were affiliated to, inspired by, directed by or linked to extremist networks.
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