Is zakat obligatory on money saved in the Voluntary Takaful Fund, and how is its zakat calculated for past years?

Takaful funds among employees fall under the category of cooperation in righteousness and piety. They must be established in accordance with Sharia rulings, and participants must adhere to Sharia guidelines. As for the zakat on the money saved therein, it becomes obligatory if it reaches the nisab and a full year has passed over it.