Colorado would drop income tax, sales tax and the tax on buildings, and fund the state with one annual fee on land. The fee depends on two things: how much ground you own and how many people live around it. Type your address to see your bill.
Every place pays on the same curve. The fee rises faster than density, so the pressure falls on empty ground where many people live.
People per square mile comes from the 2020 Census for each of Colorado's 1,447 census tracts: residents divided by land area, water excluded. Everyone in a tract pays the same rate per square foot. Density changes only when a new Census comes out, once every ten years, so everyone can plan ahead.
The constant, 0.0000107, is set so the fee raises about $40.5 billion a year, the amount the proposal estimates Colorado collects today. Change the constant or the exponent and every landowner's bill moves together.
Addresses are found in Colorado's statewide address records, then the U.S. Census address lookup. Land size comes from the parcel records counties share with the state; about 20 mostly rural counties don't share them yet, so enter your acreage there. Federal land can't be taxed by the state. A tract with no residents, such as Denver International Airport, uses the density of the tracts that touch it, so no ground is left out.