In the first decade following the founding of the British Labour party, the number of people regularly voting for Labour increased fivefold. The number of committed Labour voters increased a further fivefold during the party' s second decade. Since the increase was thus the same in the first as in the second decade, the often-made claim that the Labour party gained more voters in the party' s second decade than in its first is clearly false. The reasoning in the argument is flawed because the argument ['relies on statistical evidence that, strictly speaking, is irrelevant to establishing the conclusion drawn', 'fails to allow for the possibility that the policy positions advocated by the Labour party changed during the period in question', 'fails to specify dates necessary to evaluate the truth of the conclusion, even though the argument depends on distinguishing between two time periods', 'draws a conclusion that cannot be true if all the data advanced in its support are true']