Fig. 4

Effect of vaccinations on CO emissions per capita, at different lags. Coefficient \(\beta\) is reported for each lag ℓ (1–40), and based on \(\Delta {Y}_{i,t}=\alpha + {\mu }_{i}+{\gamma }_{t}+{\beta SV}_{i,t-l}+ {\theta X}_{i,t-l}+ {\varepsilon }_{i,t}\) for a sample of 44 countries using daily data from December 20, 2020–June 16, 2021. \({Y}_{i,t}\) denotes CO emissions per capita and \({SV}_{i,t-l}\) is the surprises in vaccines administered (per capita).\({\mu }_{i}\) and \({\gamma }_{t}\) are the country and time fixed effects. X is a vector of control variables which includes the level of new cases, NO₂ and CO emissions per capita, the stringency of containment measures index, and mobility indices at t-1. Lightly shaded bars denote 90 percent confidence bands, and dark-shared bars denote 95 percent confidence bands