You must be careful. Too easily those numbers can be based on simple things like reporting differences.
I know one case where one town had a lot more missing children then another - and after a big outcry, the problem was easily resolved:
Town A had reported children missing if e.g. the parents reported them missing at the police.
Town B had them officially reported as missing when the children did not come home for 24 hours after the parents called the police, which makes sense, since 95% are found inside a few hours.
So town A changed to the reporting method of town B and voila, problem solved!
Please read parts 1-3, where I address this notion and more.