Formatting time since state change

I am trying to retrieve the moment of state change of a service or host. This works well as far as I want it formatted the same way as the header of monitoring/service/show… but I want the point in time.
So not since 5m but instead 2019-03-11 18:15. I checked out the rendered HTML and there is indeed a title behind the header label which tells me this exact information but I was unable to find where it is generated.

Can someone help me telling me how to get this information?

You are probably looking for this:

for example in any view script (phtml):


Thanks. That was exactly what I was looking for.