Abstract
The use of a restricted number of mechanical counts offers the possibility to prepare and organize an extensive visual data collection. Once by means of peak hour factors and sub factors the representativeness and reliability of week days have been calculated, it is quite simple and cheap to choose the most suitable days for data collection. The choice of the number of days depends mainly on the pursued percentage of weeks with rush hour intensities with a Poisson distribution. Although this article is restricted to the preparation of mechanically collected data on rush hours and conclusions therefore are being drawn concerning the days in question, it is also possible to extend the application to a different time scale.