How is the zakat calculated for commercial land that could not be sold for two years: Is it from the profit, or from the purchase price plus the profit, or from the purchase price?

If the land is prepared for sale and trade, Zakat (definition) is obligatory on it at the end of every year (hawl) if its value reaches the nisab (definition), either by itself or by adding money or other trade goods to it. Its hawl is the hawl of the money with which it was purchased. Zakat for the past two years must be paid if the land's value reached the nisab at market price, and Zakat is paid from the total capital and profit.