As we were saying, J Bradford...

Somewhere around a decade ago, that you would have to choose what you really want; a tax system that is progressive in form (high marginal rates on higher incomes), or one that is progressive in substance (the one that we have since Reagan);

One the one hand, a clear picture emerges from our findings. Effective tax rates on most households are relatively low (below 10%) and differ substantially from those at the top. For instance, married household around median income experience tax rates around 4%, while those at the top 1% face tax rates of around 23%. Furthermore, taxes paid are concentrated at the top. In a nutshell, the provisions in the law, in conjunction with the observed dispersion in income lead to the finding that the bulk of tax payments are concentrated in upper income households and that a large fraction of US households have effectively no tax liabilities. From this perspective, the answer to the question above is that there is substantial progressivity in the tax burden as measured by effective, average tax rates. Put differently and in plain terms, moving a hypothetical household along the income ladder implies substantial increases in average tax rates.

On the other hand, tax rates at the top of the income distribution are essentially constant as income changes. Once high income levels are reached, effective tax rates do not change.

Elsewhere in the piece is the information that the top 1% of earners pay about double 'their share' of taxes.  I.e., they earn about 20% of the income and pay a little less than 36% of the taxes.