Taxes are the primary way we pay for the things that we do together through government. These include things like police and fire protection; public education; roads, bridges and public transportation; a safety net for when people face hard times; and more. Determining how much people at different income levels pay in taxes is important when considering the fairness of tax policy changes. While most taxes in Massachusetts have a fixed rate—for example, the state has a flat 5.15 percent income tax—different income groups are affected differently by each tax. These differences can be explained in terms of regressivity and progressivity—how taxes vary by income level.