Information content of earnings announcements in the New Zealand equity market, a longitudinal analysis

We compute abnormal return variance and abnormal trading volume in the 3-day window surrounding earnings announcements to examine the information content of earnings announcements in the New Zealand equity market over the past 16 years. We find that the information content of earnings announcements has increased significantly over time, and this finding holds true for both interim and preliminary earnings announcements. We find evidence that earnings announcements with June year-ends exhibit a higher level of information content and experience a more pronounced rising trend as compared to earnings announcements with non-June year-ends. Several firm characteristics appear to relate to the level of the information content of earnings announcements as well as to compound the trend over time. We document an important finding that the information content of earnings announcements increases remarkably in the period after the adoption of the International Financial Reporting Standards (IFRS).