(a) If you want to consider the grouping option, you must have data:
(1) on the size of each service group in the number of service units operated during the period for which the sample data were collected, and
(2) on the expected size of each service group for future sampling years.
(3) Follow the instructions in the template on how you should enter the information on group size.
(b) If you want to consider combining the grouping option with the APTL option, you must enter into the template whether you will have reliable 100% counts of UPT for each service group for estimating your annual PMT. Follow the instructions in the template on where you should enter this information. Your input affects several things:
(1) The efficiency of your sampling plan. In general your sampling plan is more efficient if you will have reliable 100% counts of UPT by service group.
(2) How you should estimate your annual PMT. For example, you will need to estimate your annual PMT separately for each service group if you have 100% counts of UPT by service group. Refer to Subsection 83 for more guidance on estimation.
(3) The information you need to get from the template for determining whether you need to revise your template sampling plan. Refer to Subsection 56 for more guidance on revision of sampling plans.
(c) If you want to consider interval-based sampling plans, you must have information on the annual number of days of service and the daily number of trips.