### Calculation of Tourist Demand

The calculation of tourist demand per Demand Centre uses the following formula:

 TWD = BU * (twdb * 30 / 1000) * OR / 100 with TWD = Tourist Water Demand (m³/month) BU = number of Bed Units twdb = Tourist water demand in litre per bed unit per day 30 = factor to convert from day to month 1000 = factor to convert from litre to m³ OR = Occupancy Rate in % 100 = factor to convert from Percentage to fraction

In the above formula, the number of bed units, the occupancy rate and the tourist water demand in litre per bed unit will change for future scenarios. While the occupancy rate and the tourist water demand in litre per bed unit are set manually, for the number of bed units the general concept of growthrate and migration is valid again.

Thus, the number of bed units is calculated as follows:

 Bn = Bb * (1 + G / 100)N + S with Bn = Bed units at the new year Bb = Bed units at the previous time step G = yearly Growth rate in % 100 = factor to convert from percentage to fraction N = N = (2005 - reference year), for the next steps: N= 5 ( 2010, 2015 etc.) S = sudden increase/decrease of bed units