It is a 5 Swiss franc coin from 1979.
So your birthday is 3 June 1979.
So, unless you are unlucky (or perhaps lucky, depending on what might happen otherwise), you will be around for quite some time. Probably, you have not yet lived half your life (as a German male presently has a life expectancy of 78).
"A wise man ... proportions his belief to the evidence."
— David Hume, An Enquiry Concerning Human Understanding, Section X, Part I.