Determinants of Voluntary Disclosure in Annual Reports of Nigerian Listed Firms: A Governance Perspective

This study investigates the governance and firm-level determinants of voluntary disclosure in the annual reports of companies listed on the Nigerian Exchange Group. Voluntary disclosure, which encompasses information beyond mandatory regulatory requirements, is theorized to reduce information asymmetry, lower the cost of capital, and improve stakeholder relationships. Understanding what drives voluntary disclosure in the Nigerian context is important for regulators and investors seeking to improve market transparency. This study uses content analysis of the annual reports of 48 listed firms across banking, insurance, manufacturing, and services sectors for the period 2019 to 2023. Voluntary disclosure is measured using a 72-item index covering strategic, operational, financial, and non-financial categories. Governance determinants include board independence, audit committee expertise, ownership concentration, and Big Four audit firm affiliation. Firm-level controls include size, leverage, and profitability. Tobit regression is applied to address the bounded nature of the disclosure index. Results indicate that board independence, audit committee expertise, and Big Four affiliation are the strongest positive determinants of voluntary disclosure. Ownership concentration shows a significant negative relationship, consistent with substitution theory. Larger and more profitable firms disclose more voluntarily. The study concludes that governance quality is the primary driver of voluntary disclosure in Nigerian listed companies. It recommends that FRCN strengthen minimum governance disclosure requirements and introduce voluntary disclosure benchmarking frameworks to encourage competitive transparency improvements.

Keywords: voluntary disclosure, corporate governance, annual reports, Nigerian Exchange Group, Tobit regression.