On 30 September 2017, Penang Berhad, a listed company had 8 million ordinary shares amounted to RM4 million. Two months later, on 1 December 2017, Penang Berhad consolidated two existing shares into one share. On 31 March 2018, the company issued 2 million ordinary shares at a price of RM2 per share. On 30 September 2018, the company make a right issue of 1 share for every 5 outstanding shares. The last exercise date for right issue was on 1 May 2019 and the exercise price would be RM3.50 per share. After that, on 1 January 2019, Penang Berhad issued fully paid up 500,000 convertible preference shares at RM4 per share. On 30 September 2019, 100,000 preference shares were converted into ordinary shares at a rate of 1 preference share for 3 ordinary shares. On 1 August 2020, the company purchased back 300,000 of its issued ordinary shares at a price of RM4.50 each. The profit after tax attributable to shareholders of Penang Berhad was RM4.1 million, RM4.3 million, RM4.7 million and RM5.2 million for financial year ended 30 September 2017, 2018, 2019 and 2020 respectively.

The corporate tax rate is 24%.

Required: Calculate the basic earnings per share for Penang Berhad as at 30 September 2017, 2018, 2019, and 2020. Show all your workings and please explain the results!