Generally, call intervals are used as guidelines for portatour®, which deviates the effectual call intervals slightly in order to optimize routes and minimize driving distances. Very decentralized locations or heavily restricted business hours of a customer can all have an impact on meeting the call interval. Furthermore, overall compliance to all call intervals depends on the number of customers and the size of the territory. If you have too many customers and there is not enough time to keep up with the call intervals you have set as a goal, portatour® will internally and automatically increase the call intervals as required. However, the ratio remains the same, e.g. a 30-day-customer will be visited twice as often as a 60-day-customer. If, on the other hand, the number of customers is too low, portatour® will equally reduce the call intervals but still take the lower limit of call urgency into account (see section Urgency). This could lead to a 30-day-customer being visited every 25 days.