A computer-implemented method for processing loading operation data to estimate one or more delivery events is described. The loading operation data comprises payload records, each representing a delivery event. The method comprises, for a selected payload record, operating a processing unit to determine whether a delivery weight in respect of the selected payload record is likely to reflect a single delivery event. If the delivery weight is unlikely to reflect a single delivery event the method further comprises generating a synthetic payload record representing an estimated delivery event and comprising synthetic weight and timing values.