States there is a need for a more effective way of thinking about the cooling loads created by ventilation air. Proposes a 'ventilation load index' (VLI) as the total load generated by one cubic foot per minute of fresh air brought from the weather to space-neutral conditions over the course of one year. It consists of two numbers, separating the load into its dehumidification and cooling components - latent ton-hours per cfm per year and sensible ton hours per cfm per year. Proposes the VLI index in the same spirit as the use of degree days. Describes the calculation process, referring to locations throughout the USA.