Average Daily Ridership
It is useful to know the total number of passengers traveling on average each day. In most cities, the number of passengers traveling on working days is significantly higher than at weekends. It is the peak hour weekday figure that determines the required capacity of the bus system.

The figure normally quoted is the number of passenger boardings per day (which is normally termed passengers per day). Most bus users will make at least two trips daily (to and from work), and many will have to use more than one bus to make one trip. Thus a passenger making two boardings per trip would make four boardings daily. The number of daily passengers, therefore, is normally much higher than the number of people who travel every day.

For a formal bus operation, passenger statistics are usually derived from the ticketing system, which normally records the number of tickets issued. The regulatory authority should require that daily ridership figures are reported on a route by route basis at weekly or monthly intervals. Usually, figures quoted as the number of passenger boardings are in fact the number of tickets issued. There may be discrepancies if not all passengers are correctly issued with tickets, or, as is sometimes the case, where two or more low-value tickets must be issued for a high-value fare, for which the correct value of ticket is not available. In these cases surveys should be carried out to establish factors for each route to convert numbers of tickets sold into passengers and these factors should be updated from time to time.

In many cities in developing countries, where some or all bus services are operated less formally, and no tickets are issued, ridership figures are not readily available, and must be determined by surveys.