1. A computer-implemented method for processing loading operation data to estimate one or more delivery events, the loading operation data comprising a plurality of payload records, each payload record representing a delivery event, wherein 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, the determination being based at least in part on an estimated loading machine payload weight; if the delivery weight is unlikely to reflect a single delivery event, generate a synthetic payload record representing an estimated delivery event, the synthetic payload record comprising: a weight value representing an estimated haulage machine payload weight at the estimated delivery event, and a timing value representing an estimated time at which the weight value for the synthetic payload record would have occurred, and update the loading operation data by incorporating the synthetic payload record into the loading operation data.