Jimmy Savile spent 'every waking minute' thinking about abusing boys and girls He said Savile's "offending footprint" was "vast, predatory and opportunistic." The report says there is no evidence that Savile was part of a paedophile ring, though he could have been part of an "informal network." Detective Superintendent David Gray, the leading investigator, said: "He spent every minute of every waking day thinking about it whenever an opportunity came along he has taken it. He is programmed to think and act in that way. He only picked the most vulnerable, the ones least likely to speak out against him. Savile preyed on 450 victims, aged between eight and 47, over a 54-year period. Almost a fifth of his victims were boys. One of the most striking figures in the report relates to the number of children under 10 who were abused by Savile. A total of 18 girls and 10 boys under the age of 10 were abused by Savile, with 23 girls and 15 boys aged 10 to 13. Savile's earliest reported offence was in Manchester in 1955. He went on to sexually abuse children at the BBC from 1965 to 2006 - the date of the final Top of the Pops; at Leeds General Infirmary, where he volunteered as a porter, from 1965 to 1995; at Stoke Mandeville Hospital, where he was also a porter, from 1965 to 1988, and at Duncroft School between 1970 and 1978. Other offences were committed at Broadmoor secure hospital, where he had his own room, at his holiday cottage at Glencoe in the Highlands and in his mobile home. Savile was investigated by police five times while he was still alive - by the Met in the 1980s and in 2003, by Surrey Police from 2007 to 2009, by Sussex Police in 2008 and by Jersey Police in 2008, but none of them resulted in charges. The Crown Prosecution Service has today released a separate report into its reasons for deciding not to press charges. Peter Watt, NSPCC director of child protection advice and awareness, who co-wrote the report, said the scale of Savile's abuse "simply beggared belief." The two most prolific years of his offending were 1975 and 1976, with 15 offences committed in each year. Savile, who died in October 2011 aged 84, almost certainly abused more than 450 people, as "others will also have experienced abuse but have chosen not to speak out," the report says. It describes his "peak offending period" as between 1966 and 1976, when he was aged between 40 and 50. Most of his victims were aged 13 to 16, with 82 per cent of them female and 18 per cent male. Almost three-quarters of the victims - 73 per cent - were aged under 18. The report suggests that part of the reason Savile was never caught was because at the time he was most active, "police investigation of such crimes was more basic and lacked the specialist skills, knowledge and the collaborative approach of later years." The report says that a "significant number" of other suspects have been identified, and Operation Yewtree continues to investigate alleged abusers who either knew Savile or operated alone. The report says that 57 alleged offences by Savile happened on hospital or hospice premises, with 33 in TV or radio studios and 14 in schools. Of the 34 rape offences, 26 victims were female and eight male. The report also includes examples of the way Savile targeted his victims. In 1960 a 10-year-old boy saw Savile outside a hotel and asked for his autograph. They went inside the reception where the boy was seriously sexually assaulted. In 1972, during a recording of Top of the Pops, a 12-year-old boy and two female friends were groped during a break in filming, and in 2009 a 43-year-old woman was talking to Savile on a train journey between Leeds and London when Savile put his hand up her skirt. The report concludes: "Perhaps the most important learning from this appalling case is in relation to the children and adults who spoke out about Jimmy Savile at the time. Too often they were not taken seriously. We must not allow this to happen again - those who come forward must be given a voice and swift action taken to verify accounts of abuse. The report says that Savile committed offences at 14 hospitals, including a Sue Ryder hospice in Leeds and Great Ormond Street children's hospital in London. As well as Broadmoor, he also committed an offence at Ashworth NHS High Security Unit. He committed 22 offences at Stoke Mandeville and 16 at Leeds General Hospital. The other NHS hospitals involved, where one offence was reported at each, were Broadmoor; Ashworth; St James Teaching Hospital, Leeds; High Royds Psychiatric Hospital, Leeds; Dewsbury Hospital; Wycombe General, High Wycombe; Great Ormond Street; Exeter Hospital; Portsmouth Royal Hospital; St Catherine's Hospital, Birkenhead and Saxondale Mental Health Hospital, Notts. The Sue Ryder Hospice where he committed one offence in 1977 was Wheatfield Hospice in Leeds. The report adds that Savile committed offences at four schools, where he would be invited as a guest after featuring their pupils on Jim'll Fix It.