Application data is reported in response to monitoring an application transaction. Application data is obtained for an initial period of time. A function which estimates the application data is then identified for the reported application data. After identifying the function, subsequent application data is obtained, and function data is generated from the subsequent application data. The function data may be associated with function parameters associated with the identified function. A function can then be constructed from the reported function data. The function constructed from the function data may estimate application data associated with the monitored transactions.