Time period of the stats in Info command

[amoghgarg]

The INFO command has the commandstat section which includes number of calls that reached command execution.

My question is this count of calls is over what period? Is this over last 1 minute? Over last 1 hour? Since the server started?

When I plot this value, it is not a increasing value. It increases and decreases. So it does not seem to be since the server started.

Based on the number of calls, it could be over the last 1 hour. But I can not confirm from the documentation.