The inclusion of international corporate taxation goes beyond the scope of our study, and this subject should be subject to future research.
American policy makers might consider global taxation treaties, to reduce the scope for tax competition.
As a result there would be scope for devolved taxation to raise 40% of the Scottish parliament's expenditure.
Beneath the mechanics lie deeper philosophical disagreements about spending, taxation and the size and scope of government.
However, these studies were more limited in scope and did not include taxation and GDP costs.
Speaking at a meeting of finance ministers on Wednesday, the European commissioner responsible for taxation, Laszlo Kovacs, said he would propose extending the scope of a directive on the taxation of savings, which applied primarily to bank accounts.
Republican campaigns tend to ride national waves, running on broad national issues like the size and scope of government, the level of taxation and the defense of the homeland.
However, when attempting to make any rudimentary analysis of income, consideration must also be given to overtime pay, working hours per week, cost of living, taxation, and job satisfaction, which is beyond the scope of this study.
Many of the compromises limited the scope of decision-making in sensitive areas like taxation and social issues.
Mr Roy-Chowdhury, head of taxation at the ACCA accountancy body, said: "There is huge scope for people to be underpaying tax inadvertently".
