Nataraj​ (2007) finds that a 100100​% increase in the price of water for heavy users in Santa Cruz caused the quantity of water they demanded to fall by an average of 2020​%. ​ (Before the​ increase, heavy users initially paid ​$1.551.55 per​ unit, but afterwards they paid ​$3.103.10 per​ unit.) In percentage​ terms, how much did their water expenditure​ (price times ​quantity)long dash—which is the water​ company's revenuelong dash—​change?