doing so would help to ensure orderly payments of ageingrelated expenditures such as healthcare costs in a recent study it was found that given a currently low taxtogdp ratio there is significant room to raise taxes without causing major economic distortions in china japan and the republic of korea poesoro recent efforts to increase tax revenues in the subregion include the sales tax increase in japan in the republic of korea is considering adding another income tax bracket at the top end of the pay scale