Income tax in the United States increase complexity, irrespective of the system's flatness or lack thereof. Income tax is also levied by most U.S. states and many localities on individuals, corporations, estates, and trusts. These taxes are in addition to federal income tax and are deductible for federal tax purposes. State and local income tax rates vary from 1% to 16% of taxable income. Some state and local income tax rates are flat (single rate) and some are graduated. State and local definitions of what income is taxable vary highly. Some states incorporate the federal definitions by reference. Taxable income is defined separately and differently for
Working Tax Credit Prime Minister Tony Blair also apologised to Parliament over the incident. The Working Tax Credit scheme was subject to much criticism, particularly in the wake of the difficulties surrounding its implementation. Criticism focused on the way that credits are calculated on an annual basis, leading to overpayment, followed by large demands for repayment, which those on low income may find difficult to meet. David Harker, chief executive of Citizens Advice, commented "This is an untenable system. An annualised system doesn't provide the stability of income required by low income families." In addition, the scheme was accused of being over-complicated and