i've been hearing of how people reduced their age in school and sometime when applying for a job. and some others who'll obtain court order to reduce their age and set a new date of birth after they had finished secondary school. and i can still remember how my brother who is five years older than i am is using my age in his credentials.

but due to the jump jump and skip skip i did during primary and secondary school. i can't reduce my age in my credentials any longer. cos any slight change my age may be questionable in regard to my ssce exam year and so i left it.

but will it ever matter if i didn't change or reduce it?

I don't think it will matter.
Some change it for some reasons known to them.

Why should age even be on your cv?