The impact of MILA market-maker facility on volatility of the Colombian stock market

ABSTRACT In 2014, the Colombian Stock Exchange commenced the implementation of its market-maker facility (MMF), aiming at improving market efficiency. This paper examines the impact of the MMF program on three volatility-related aspects: volatility persistence, risk premium, and information asymmetry. This paper provides new insights about the anticipated outcomes of Mercados Integrados Latinoamericanos (MILA) reforms, specifically the MMF on the volatility of the Colombian stock market. This topic has not been fully addressed in the existing literature. This study, therefore, provides useful information for regulators and policy makers, in endeavors to address key issues raised during the World Economic Forum (WEF) of 2016. This paper poses a challenge to policy makers and stock market regulators in Colombia to revisit the reform program and address the factors limiting the effectiveness of market reforms. This paper provides justification for replicating the study to cover other MILA countries due to existing differences in some domestic market policies and structures. The paper employs conditional variance models for measuring volatility persistence, risk premia, and information asymmetry. The models are employed on the COLCAP stock index (Colombia) observed from January 17, 2008 to May 30, 2019. Observations are divided into two samples - pre- and post-MMF. This paper provides evidence of the impacts of the MMF reforms in the Colombian stock market. Specifically, the MMF seems to have an impact on the following aspects: (i) the magnitude in which current returns depend on previous returns has increased; (ii) investment portfolio returns, which are generally low, have declined after the MMF, leading to less risk compensation; (iii) the MMF does not seem to have affected the volatility of market returns and information asymmetry; (iv) volatility persistence increased in magnitude.