I love how people do this, they have a theory and they make a statement to back that up, lets break yours down. Manchester is not top(that would be Blackburn 1762 per 100,000(Manchester is 5th)so you are 0-1 there then you mention its due to young people that would assume that Manchester has a young population in relation to other cities and towns.... not the case Manchester actually doesn't rate in the top 20 although interestingly Manchester at 38 is older than Blackburn at 37 so 0-2. The spike within the UK might well be caused by the 20-30 age group, but claiming Manchester is proof of that isn't something that holds up to examination