Giving more than 20% to charity

I realized that I gave more than 20 percent of my money to tzedaka this month,do I have to stop giving tzedaka untill next month.also can I calculate the percentage of tzedaka that I give from the start of the jewesh year untill the start of the following year or do I have to calculate the monthly percentage if I get payed monthly and not annually ( I get payed the same amount every month throughout the year)also if I don't know how much I have given so far this year can I start calculateing starting now even if it might end up being more. I am not a wealthy person but I have a steady income but I only know I will for sure have this steady income for the next couple of years( the contract I have now only is untill 2025 and then will have to be renewed and it's not a sure thing that it will be renewed but hopefully it will be.

Hello there,

Our sages prohibited a person from giving more than 20% of his money to charity, unless he is extremely wealthy.
The reason for this is to prevent him from becoming poor himself and needing to receive charity.
A person can give more than 20% in one month and calculate what has already been paid in the following month.
You can decide to pay monthly or according to annual income, whichever is more convenient for you.