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We analyze whether noncooperative collusive equilibria are harder to sustain when individual demand levels are not fixed but are able to fluctuate. We extend a Bertrand-type model of price competition to allow for fluctuating market shares when prices are equal. We find that, the larger the market share fluctuations may be, the higher the discount factor should be to sustain a collusive equilibrium in trigger strategies. When individual demand in the collusive state is low, the gains from collusion go down. Moreover, the firm with the low demand can capture a larger share of the market by deviating from the collusive strategy. The incentive to deviate therefore becomes larger when individual demand decreases. An equilibrium explanation for price wars is given by a specific type of semi-collusive equilibrium. We find that there exist equilibria in which competitive periods (price wars) occur with probability 1 and on the equilibrium path.