For production and sales, it is important to know how the product demand is evolving. In long supply chains with high-priced or poorly storable goods, precise demand planning is crucial. Qualitative methods such as expert opinions, surveys, past-time experience or quantitative methods are usually used. Quantitative demand planning and the associated data acquisition and analysis became more important with increasing digitalization. Using data from search engine requests or social networks, global and regional trends can be predicted and included into production planning. Operational data from customer cards or sales lists can be used to determine changes in customer behavior. To rely on external data sources is no longer necessary. The better the data analysis becomes, the more important it will be for companies to acquire data out of their own processes.