and c 3 respectively to central authority 20 as shown a network interface 70 within casino c 1 transmits the progressive jackpot data from casino c 1 to network interface 24 in central authority 20 via network 30 in a well known manner a network interface 72 within casino c 3 transmits the progressive jackpot data from casino c 3 to network interface 24 in central authority 20 via network 30 in a well known manner interfaces 70 and 72 may be identical all the progressive jackpot data from casino c 3 is transmitted over a single set of communication lines 34 to central authority 20 the progressive jackpot data received from casino c 1 over lines 32 is stored in monitoring computer 40 and the progressive jackpot data received from casino c 3 over lines 34 is stored in cpu 60 still referring to fig3 casino c 3 includes an exemplary gaming machine gm 9 within group gr 9 and an exemplary gaming machine gm 10 within group gr 10 machine gm 9 is coupled to a conventional gaming interface gi 9 and machine gm 10 is coupled to a conventional gaming interface gi 10 gaming machines gm 9 and gm 10 may be constructed like machines gm 1 and gm 2 and interfaces gi 9 and gi 10 may be constructed like interfaces gi 1 and gi 2 each of gaming machines gm 9 and gm 10 generates progressive jackpot data for multiple progressive games the progressive jackpot data is stored in progressive jackpot meters that form part of each gaming machine gm 9 and gm 10 for example machine gm 9 includes progressive jackpot.