GGR is the standard measure of gambling activity, used by regulators, tax authorities and the operators themselves. The definition is one subtraction: everything staked, minus everything returned as winnings. It excludes operating costs, so it is not profit; it is the raw output of the house edge applied to the volume actually played.
The measure has a mirror worth noticing: an industry announcing record GGR is announcing that players collectively lost a record amount, because the two are the same figure with different labels. Most gambling taxes and levies are set as a percentage of GGR, which is why regulators publish it and why market sizes are quoted in it.
Why it matters
GGR is the honest unit for reading any claim about the gambling market: it converts industry growth stories into what they also are, the total spent by players. It is also the base most gambling taxes are computed on.
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