<p>Since the seminal work by Diamond and Mirrlees (1971), various attempts have been made to calculate optimal tax rates for different countries (e.g. Deaton (1977) for the UK and Harris and McKinnon (1979) for Canada). Other exercises along these lines are studies by Ebrahimi and Heady (1988), who examine the sensitivity of optimal tax rates to assumptions regarding separability and the availability of optimal demogrants, and those of Fukushima (1991) and Fukushima and Hatta (1989), who examine the welfare implications of a move to uniform taxation.</p>