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However , the tax system more generally has become less progressive over the past two decades and changes to the federal tax code made within the past year exacerbate this trend . Moreover , it could help exacerbate the global environment issues such as desertification and global warming . Does the ethnic impact of transnational migration exacerbate Japanese and Taiwanese exclusionary notions of national identity ? Weaknesses in the Office of Institutional Research and the lack of a relational database management system exacerbate this problem ( page 61 ; see rec 1 , 2 , 3 , and 5 ) . Countries differ in the types of information they require to be kept , and in some cases ambiguous and vague rules exacerbate the difficulty .