A system and methods for estimating the size of a parcel based on a mathematical formula derived from other parcels within a size category. The system may include a variety of modules in communication with a relational database for storing data related to parcels being delivered. Similar data may be retrieved from a variety of sources with embodiments of the present invention prioritizing the data based on the reliability of the source. In a further aspect, equipment needs are forecasted by evaluating parcel data over a period of time.