SmartLoop Posts are not counted on a monthly or annual basis. Since SmartLoops can continue indefinitely, the posts are not counted by how many individual publishing actions are performed, but on how many Pins are Pinning to different Boards.
Each Board a Pin is set to loop to counts as 1 Post, regardless of how many times SmartLoop is actually publishing that Pin.
For example, a single Pin looping to 10 Boards counts as 10 SmartLoop Posts, regardless of how often it actually gets published in the Loop.
You can see how many SmartLoop Posts each Loop is using on the Your Loops section of your dashboard.
Do you need additional SmartLoop Posts? Get more by purchasing a SmartLoop PowerUp! You can learn more about SmartLoop PowerUps in our Knowledge Base article: How much does it cost to use SmartLoop?