Bonus income for holding bonuses continuously.
Be able to receive a bonus income for holding a territory bonus. It can grow larger each turn after a certain number of turns, or just add income after holding a bonus for a certain amount of turns. Say a player holds the China bonus. If he holds it for 5 turns straight ( or any number of turns set by host), he can get a static bonus of a few army income or have the bonus grow larger over the turns. If the China bonus is broken, the bonus income for holding it for 5 turns is broken as well.
Completed as mod "Dynamic Bonuses"