How is Zakat calculated on variable capital in contracting work?

Money must be considered. If it reaches the nisab (definition) (minimum threshold) by itself, or by combining it with other money or trade goods, and the nisab is equivalent to the value of 85 grams of gold, then once the money reaches the nisab, a full hawl (twelve lunar months) must be calculated starting from the day it reached the nisab. If the hawl passes and the money has not decreased below the nisab, then zakat (definition) must be paid at a rate of 2.5% of the principal amount and its profit, in addition to trade-related debts that are expected to be recovered. Debts owed by the individual are deducted, unless they possess non-zakatabale assets equivalent to these debts.