State rent, also known as storage rent or state fees, requires users to prepay rent for storing data on the blockchain. The amount of rent paid is proportional to both the size of the data and the amount of time the data is stored on-chain; many different models of charging rent have been suggested with no clear winner. By making the user rather than the full node pay for the cost of state, this prevents state bloat by ensuring that unused information falls out of the state over time.