Elapsed time of a snap

I’m trying to find the start/end timestamps and elapsed time of a REST Post snap for a single request using the Runtime API.

In Postman, I supplied the following:

What am I supposed to be looking for to extract the necessary timestamps?
Is “snap.out_time_ms” what I should be looking at?
What is “in_time_ms”? It doesn’t “translate” into a realistic timestamp or elapsed time.
“in_time_ms”: 1305003,

“out_time_ms”: 6,