And about 60 % of them are in an age between 18 to 39 .
This defines a subset of 3 to 4 % of the overall group of people that are active in walking , jogging , hiking or climbing .
About 60 % of them are in an age between 18 to 39 .
This defines a subset of 3 to 4 % of the overall group of people that are active in walking , jogging , hiking or climbing .