Extremely misleading site associated with right wing "Heritage Foundation".
Example of one of the lies this site spreads is a recent article titled "Opposite the Headlines, Income Inequality has Gone Down over the Last Two Decades".
This site provides many different fully sourced reports on taxes. No agenda, just data. You can use that to form your own opinions. If you have questions about how much tax was collected, how much a certain group paid, how it was spent, etc. this site most likely has the information.