If you choose the Occurrences rating method using the above entries, each occurrence would be charged the per minute rate as calculated using the initial amount and the rate seconds.
For example, if you enter 180 in the rate second field, the IDI platform figures the per minute rate which is the dollar amount entered in the initial amount field divided by 3 (180 seconds in the rate seconds field).
Rating Method=Occurrences
Then, if you enter:

and

The associated call is rated at $0.0267 (or $0.0266 depending on your rounding options).