A controller for use in monitoring at least one operating wind turbine is communicatively coupled to the at least one operating wind turbine, to a server sub-system, and to a user interface device. The controller is configured to receive operational data from the at least one operating wind turbine and select at least one formula based on the received operational data, wherein at least one of a predetermined formula is selected, a formula is selected via the user interface device, and a formula is selected via the server sub-system. The controller is further configured to determine at least one site level parameter using the at least one selected formula, and transmit at least one of operational data, the at least one selected formula, and the determined parameter to the server sub-system.