The plant and machinery account (at cost) of a business for the year ended 31 December 2020 was as follows: 2020 1 Jan Balance b/f 30 Jun Cash purchase of plant $ 2020 $ 240,000 31 March Transfer to disposal account 60,000 160,000 31 Dec 400,000 Balance c/f 340,000 400,000 The company's policy is to charge depreciation at 20% per year on the straight-line basis, with proportionate depreciation in the years of purchase and disposal. What should be the depreciation charge for the year ended 31 December 2020?