The meaning of "a balance is struck at intervals"

According to this link, "a deposit book is the book held by a depositor in a bank in which are entered the sums placed to his credit and in which, when a balance is struck at intervals, the amount of the debits also is entered." Could someone help me understand the meaning of "a balance is struck at intervals" in this context?

I did a search and "strike price intervals" was what I found, but I don't think one thing has to do with another in this case.

Thank you!

The expression is:

strike a balance (in the financial sense)

Find a compromise, as in We have to strike a balance between what we want and what we can afford. This expression alludes to accounting, where it signifies finding a profit or loss by weighing income versus outlay. [Mid-1800s]

(AHD)

When balance is struck at intervals that is when you calculate the balance between debits and credits at intervals, that is every 1, 3 or 6 months for instance.