How is Zakat paid on savings accounts, current accounts, and shares that have not changed in value for years?

The time when the wealth reaches the nisab (minimum threshold) must be known. If a hawl (lunar year) passes over it without its value dropping below the nisab, then a quarter of it is to be paid as zakat. Profits generated from a savings account in an Islamic bank are subject to zakat along with the principal, whereas in a usurious bank, the interest must be disposed of by spending it on general Muslim welfare. Regarding monthly salaries, a separate hawl can be designated for each installment, or, for ease, they can be zakat-ed along with the principal. This constitutes an advance payment of zakat for some of the money, which is permissible according to the majority of scholars. As for shares purchased with the intention of trading, their zakat must be paid for every past hawl, starting from the time the hawl was completed on the original wealth used to purchase them, provided that wealth met the nisab.