How is the Elapsed Time calculated (4273118)

How is the Elapsed time calculated for alternatives?

Is it possible to change precision to a thousandth of a second?

The Elapsed Time is calculated by subtracting the time when a SQL finished executing with the time before the execution starts.

That is:
(Time when SQL finished running) – (Time right before the SQL executes).

To get the time at a particular moment, the DBMS_UTILITY.GET_TIME package function from Oracle is used. The package function returns the current time in 100th's of a second.

This is why the Elapsed Time is also in 100th's of second in precision.