1. A method comprising: receiving, by a system, test data representing an attribute of a tested electrical device, wherein the received test data is associated with a test date on which the test data was obtained from the tested electrical device; classifying the received test data as belonging to a first client of a plurality of clients and adding the received test data to a control set representing an aggregate of information of the plurality of clients; determining whether the attribute of the tested electrical device is represented in the system by only the received test data, by only two sets of test data that include the received test data and stored test data corresponding to the attribute from at least one previous test performed on the tested electrical device, or by three or more sets of test data that include the received test data and stored test data corresponding to the attribute from at least two previous tests performed on the tested electrical device; storing the received test data if the attribute is represented in the system by only the received test data, wherein the received test data is not processed; processing the received test data using a sparse data process if the attribute is represented in the system by two sets of test data; processing the received test data using an autoregressive process if the attribute is represented in the system by three or more sets of test data; predicting a future value of the attribute based on the processing by one of the sparse data process and the autoregressive process; and outputting at least a representation of the future value.