Billing always occurs for the number of entities that are stored in your system, if on average I use two or three thousand entities per month, which is about 5.97, then in a year I will pay per month I will pay 71.64 dollars, right it turns out? and two years later, 143 dollars? Me at the time of writing off the money.
everything is right. The more entities you have, the more you pay. If you have entities that you do not use, you can delete them (for example, old events that are more than a couple of months old). The application https://1b.app/en/app/data-remove/
will help you with this.