* rate is the [[List of Pokémon by catch rate|catch rate of the Pokémon]] (which may be modified due to use of [[apricorn]] balls or actions in the [[Safari Zone]]),
* bonus<sub>ball</sub> is the multiplier for the Poké Ball used, and
* bonus<sub>status</sub> is the multiplier for any [[status condition]] the Pokémon has (2 for sleep and freeze, 1.5 for paralyze, poison, or burn, and 1 otherwise). Due to a bug in Ruby & Sapphire, if the target
Pokemon is afflicted with Toxic Poison, no catch bonus is applied. This was fixed in FireRed and LeafGreen.
If a Pokémon could have 0 HP, the maximum value for ''a'' would be rate × bonus<sub>ball</sub> × bonus<sub>status</sub>. For a Pokémon with full health and no status condition, and with a neutral ball used, the minimum value for ''a'' would be rate / 3.