They use people counting sensors at entrances and above checkout lanes/queue areas to accurately detect the number and behavior of people in the queue. Built-in predictive algorithms can provide advance notice on how many checkouts or service points will be needed to meet demand. Dashboards, available on a computer monitor or mobile PDA device, are often used to provide a range of information, such as dynamic queue length, waiting time data, and checkout performance on the shop floor. In the event that performance falls towards a minimum service level, in supermarkets or banks management teams can be automatically alerted beforehand, allowing them time to proactively manage the situation. Key measurements produced are: