Trading in the Company's shares and other financial instruments managers with a duty to notify is prohibited during a period starting at the end of each reporting period and lasting until the results release has been published (always at minimum 30 days; "closed window"). This prohibition applies not only to managers with a duty to notify but also to such other persons specified by the Company who participate in the preparation of financial reports. 

In 2018, the closed window periods are:

​Closed windowFinancial report​​Publishing date
​1 Jan–8 Feb 2018The 2017 financial results​Thu 8 Feb 2018
​1 Apr–3 May 2018Interim report January–March​Thu 3 May 2018
​1 July–2 Aug 2018Interim report January–June​Thu 2 Aug 2018
​1 Oct–8 Nov 2018Interim report January–September​Thu 8 Nov 2018​