The price of a best bid is determined, and a proposed bid sweep liquidity replenishment price is determined by subtracting five cents from the price of the best bid. The proposed bid sweep liquidity replenishment price is incrementally decreased by 0, 1, 2, 3 or 4 cents until the proposed bid sweep liquidity replenishment price is divisible by 5 without any remainder. The bid sweep liquidity replenishment price is set equal to the proposed bid sweep liquidity replenishment price. In a similar fashion an offer sweep liquidity replenishment price is determined by adding five cents to the price of the best offer and incrementally increasing by 0, 1, 2, 3 or 4 cents until the offer sweep liquidity price is divisible by 5 without any remainder.