This paper examines the readability of sustainability reporting in the annual reports, and stand-alone reports of New Zealand listed companies over a ten-year period. Sustainability reporting was manually extracted from 264 reports, and readability software was used to identify the readability scores using five readability indices. Additionally, the effects of reporting quantity, environmental sensitivity, and global listing on the readability of sustainability reporting were examined. The results show that over the ten-year period readability has improved by only 6.5 per cent, despite a substantial increase in the number of companies reporting sustainability information, and an increase in the quantity of sustainability reporting from almost a third of the companies. This research also finds that there is a statistically significant negative correlation between the average readability score and reporting quantity; meaning longer sustainability reports have lower readability scores (i.e. they are more readable). The findings indicate that environmentally sensitive companies published more readable sustainability information in comparison to companies from non-environmentally sensitive industries. However, in terms of readability, there is no difference between the reports published by companies listed only on the New Zealand Stock Exchange (NZX) and the reports published by companies listed on multiple stock exchanges. This research is the first readability study examining sustainability reporting in New Zealand. It provides companies, users of sustainability information and regulators with knowledge of the readability of voluntary sustainability reporting, showing that little change has occurred over time. It suggests a strong possibility of obfuscation and thus, a risk that sustainability reporting is sending the wrong signal to stakeholders. JEL classification: M41, Q56

中文翻译：

---

随着时间的推移，新西兰可持续发展报告的可读性

本文研究了年度报告中的可持续发展报告的可读性以及十年内新西兰上市公司的独立报告。可持续性报告是从264个报告中手动提取的，并且使用可读性软件通过五个可读性指标来识别可读性得分。此外，还检查了报告数量，环境敏感性和全球清单对可持续性报告可读性的影响。结果表明，尽管报告可持续发展信息的公司数量大幅增加，并且近三分之一的公司报告了可持续发展报告的数量，但在十年期间，可读性仅提高了6.5％。这项研究还发现，平均可读性得分与报告数量之间存在统计上显着的负相关；意味着更长的可持续发展报告的可读性得分较低（即可读性更高）。研究结果表明，与来自非环境敏感行业的公司相比，对环境敏感的公司发布了更具可读性的可持续发展信息。但是，就可读性而言，仅在新西兰证券交易所（NZX）上市的公司发布的报告与在多个证券交易所上市的公司发布的报告之间没有区别。这项研究是第一项研究新西兰可持续发展报告的可读性研究。它为公司提供 可持续性信息的使用者和监管者对自愿性可持续性报告的可读性有所了解，这表明随着时间的推移，变化不大。这表明存在很强的混淆可能性，因此，存在可持续性报告向利益相关者发送错误信号的风险。JEL分类：M41，Q56