1. A gaming system, comprising: an input device configured to receive wagers from a player to play plays of a wagering game via which the player is eligible to win first and second progressive award levels, the first and second progressive award levels having respective first and second average expected values, the first average expected value being different from the second average expected value; at least one display device configured to display the wagering game and to display a monetary value for the first progressive award level and a number of free spins of a plurality of symbol-bearing reels for the second progressive award level, the wagering game including a plurality of other symbol-bearing reels associated with a first mathematical model during a base portion of the wagering game, the plurality of symbol-bearing reels being associated with a second mathematical model different from the first mathematical model; at least one indicator on the at least one display device for displaying fractional changes between a current numerical value and a next numerical value of at least one of the first and second progressive award levels; and at least one controller configured to incrementally increase the monetary value for the first progressive award level and the number of free spins for the second progressive award level based on the plays of the wagering game, and award a current value of the monetary value and a current value of the number of free spins in response to respective triggering events.