A specialty coffee roastery in Seoul raised the retail price of its premium Geisha single-origin coffee beans from 40,000 KRW to 52,000 KRW per bag. Over the subsequent quarter, the quantity of these coffee bags purchased by consumers fell from 8,000 bags to 6,800 bags.
Assuming that the change in the quantity of coffee purchased was caused solely by the change in its price, calculate the price elasticity of demand (PED) for the premium Geisha coffee. You are advised to show your working.
