Fig. 1

Comparison of monthly sales of new energy vehicles with and without fiscal subsidies pre- or-post COVID-19 pandemic. a Illustrates the sales trajectory of new energy vehicles that received fiscal subsidies, both before and after the COVID-19 outbreak. For comparative purposes, b Shows the sales changes of NEVs that did not receive such subsidies during the same periods. In both figures, the red dashed line, perpendicular to the horizontal axis, marks the onset of the COVID-19 outbreak in December 2019. The left side of this line indicates the pre-pandemic period, while the right side indicates the post-pandemic period. The blue solid line indicates a nonlinear fit of the variable lnsales interacted with the variable mondiff. The gray area denotes the 95% confidence interval for the fit, Fig. 2 and Fig. 3  follow the same conventions.