House Bills

I keep all receipts in the house ( water,internet and electric bills ).I have an updated excel file with Pareto for yearly expense and line graph to monitor the monthly bills.I notice that electric bill drop by 20% start the month of December.I guess its because we don't use electric fan anymore.While, water bill increase by 30% for almost two months already.The only change we did is to use water container rather than a shower in taking a bath because it is cold.I think using a shower consume less water than using a water container.what do you think?