“…Many studies show that the IV curves of equity options have transitioned from a smile shape to a smirk shape since the crash in 1987; the IV curves have become more skewed to the left (Corrado and Su, 1997;Skiadopoulous et al, 2000;Cont and da Fonseca, 2002;Carr and Wu, 2003;Foresi and Wu, 2005;Yan, 2011). This smirk shape is now well accepted in the literature for US equity options; however, Guo et al (2020) show that since 2005, the smirk shape found on average seems to be driven mainly by the GFC period and that outside of this time the IV curve of SPY options represents a linear downward sloping line with very minimal curvature. There is now a vast literature examining the IV curves of international equity options (Pe ña et al, 1999;Tanha and Dempsey, 2015;Shiu et al, 2010;Li et al, 2019;Yue et al, 2020), commodity options (Soini and Lorentzen, 2019;Jia et al, 2021;Aschakulporn and Zhang, 2020) and volatility derivative options (Gehricke and Zhang, 2020).…”