Endowment Tax Fairness ActThis bill increases the excise tax on the net investment income of certain private university and college endowments. Under current law, certain private universities and colleges with 500 or more tuition-paying students (of which more than 50% are located in the United States) and endowments that are at least $500,000 per student pay an excise tax in the amount of 1.4% on the net investment income from such endowments.The bill increases the amount of the excise tax to 21% of the net investment income from such university and college endowments. Further, the bill provides that amounts collected from the increase to the excise tax on the net investment income from such university and college endowments are (1) to be deposited into the general fund of the Treasury; and (2) used to reduce the national deficit and, subsequently, the national debt.