Just want to make sure I am correct.

If using rangestat and want to include observations only from the current period, the correct notation is

Code:
interval(keyvar 0 0)
not

Code:
interval(keyvar -1 0)
or

Code:
interval(keyvar 0 1)

The second code will include observations from the previous and current periods while the third code will include observations from the current and next periods.

Just want to make sure. Thanks in advance.