Able Company received $4,800 from a customer on April 1 for services to be provided in the coming year in an equal amount for each of the 12 months beginning April. In the Able information system, these cash receipts are recorded as unearned revenue. What adjustment will Able need to make when preparing the December 31 financial statements? What is the impact on the financial statements if the necessary adjustment is not made? Is this adjustment related to an accrual or a deferral?