Negative income tax notion has long been popular in some circles, its implementation has never been politically feasible. This is partly because of the very complex and entrenched nature of most countries' current tax laws: they would have to be rewritten under any NIT system. However, some countries have seen the introduction of refundable (or non-wastable) tax credits which can be paid even when there is no tax liability to be offset, such as the Earned Income Tax Credit in the United States and working tax credit in the UK. In 1971, President Richard Nixon proposed a negative income tax as the centerpiece
Income tax in Singapore of assessment is based on income earned in the preceding calendar year. Taxation is based on the source principle, in which only income earned at source, in this case in Singapore, or those derived from overseas but received in Singapore, are taxable. Any income arising from sources outside Singapore and received in Singapore on or after 1 January 2004 by an individual (other than partners of a partnership) is exempt from tax. This system has the potential to allow for tax avoidance practiced by individuals who derive income from abroad, gain tax exemptions via their non-resident status there, and use