What is the PPLNS reward system?

PPLNS stands for Pay Per Last N Shares. This is a proportional system of rewards accrual (not static) that calculates your payments based on the number of shares you submitted during a shift.
With the PPLNS system, miners are rewarded for the loyalty to the pool because, as long as they stick with the pool consistently, they end up getting more payouts than with the PPS system.
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