Abstract
Parking measures are mostly based on surveys which are only held during a few days or less. It is hazardous to generalize the interrelationships between parking characteristics of such limited surveys. This is proved by strong fluctuations in yearly revenues from parking meters. For a certain parking site the interrelationships between revenues on one or two weekdays and total parking revenues of one week are computed. Furthermore average revenues per parking meter a week and a month are characterized in the course of which some problems of reliability are dealt with.