A charge, usually on a monthly basis, for grazing a specific kind of livestock. For federal lands, the grazing fee is based on a formula found in the Public Rangelands Improvement Act (PRIA). The federal grazing fee is equal to a base fee of [$1.23 x the Forage Value Index (FVI)] + [the Beef Price Index (BPI)] - [the Prices Paid Index (PPI)] ¸ [100] and is charged per animal unit month.