John is employed by Zebra plc. He was provided with a computer for private use on 6 November 2019. The market value of the computer when first provided to an employee for private use was £3,600 and the computer had a market value of £2,000 when first provided to John for private use. Zebra plc gave the computer to John on 5 April 2021 when it had a market value of £1,000. What are the total taxable benefits for John in respect of the computer for the tax year 2020/21?