Government statistics show that the real (adjusted for inflation) average income for families has risen over the last five years. Ttherefore, since this year the Andersen family' s income is average for families, the family' s real income must have increased over the last five years. The reasoning in the argument is most vulnerable to criticism on the grounds that the argument ["overlooks the possibility that most families' incomes are below average", "fails to take into account inflation with respect to the Andersen family's income", 'presumes, without providing justification, that the government makes no errors in gathering accurate estimates of family income', "fails to consider the possibility that the Andersen family's real income was above average in the recent past"]