As 2 states in Miami vote to allow Class 3 (Vegas-style) slot machines, the financial gain of slot machines is analysed in the local press

According to the Miami Herald, Americans put in $1 billion per DAY into slot machines as casinos generate $30 billion annually in profit from slots - with a house edge higher than most other gambling games, slots rake in approximately 70% of the total casino revenue.
The hugely recognizable 'Wheel of Fortune' slot is by far the most popular slot ever produced.

The article continues to explain the difference between Class 2 (bingo-style games) and Class 3 slots - for which the latter is more lucrative.

Slots can be both 'cherry dribblers' which offers the player more smaller wins to keep them playing, or high jackpot progressives linked across other casinos. They all share the same feature though - the 'near miss' which makes the player think they've nearly won big

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