Capacity usage trends are calculated based on historical data. By default, the longest time period taken into account for calculating the capacity forecast is 180 days. The more historical data up to 180 days are available, the more precise is the calculated forecast. Forecast calculation methods include peak calculation and average calculation, which can be set globally or customized for individual objects. Capacity forecasting is available for nodes, interfaces, and volumes that meet certain requirements, such as being managed in NPM and having enough historical data in the database. References: Monitor capacity usage trends on the network and forecast capacity issues in NPM, Forecast capacity for nodes, interfaces, or volumes in NPM, Real-Time Network Monitoring Tool