|  | Model 0b | Model 1c | Model 2d | Model 3e | ||||
---|---|---|---|---|---|---|---|---|---|
Variable | Lag (months)a | Coef. | p | Coef. | p | Coef. | p | Coef. | p |
NPI indicator | |||||||||
 Retail sales of hand hygiene productsf | 0–1 |  |  | −0.29 | 0.003 |  |  |  |  |
 Domestic airline passenger arrivalsg | 1–2 |  |  |  |  | 3.8 × 10− 4 | < 0.001 |  |  |
 International airline passenger arrivalsh | 1–2 |  |  |  |  |  |  | 1.2 × 10−3 | < 0.001 |
Other covariates | |||||||||
 Average temperaturei | 3–4 | 0.06 | < 0.001 | 0.06 | < 0.001 | 0.04 | 0.001 | 0.07 | < 0.001 |
 Relative humidityj | 1–2 | 0.05 | 0.06 | 0.04 | 0.08 | 0.05 | 0.007 | 0.05 | 0.02 |
 Intercept |  | −4.26 | 0.01 | −1.89 | 0.32 | −7.17 | < 0.001 | −5.82 | < 0.001 |
Year | |||||||||
 2014 |  | Ref. |  | Ref. |  | Ref. | Ref. | ||
 2015 |  | 0.20 | 0.52 | 0.20 | 0.51 | 0.24 | 0.33 | 0.09 | 0.72 |
 2016 |  | 0.13 | 0.96 | 0.05 | 0.86 | −0.02 | 0.91 | −0.37 | 0.16 |
 2017 |  | 0.49 | 0.13 | 0.60 | 0.06 | 0.30 | 0.24 | −0.03 | 0.90 |
 2018 |  | 0.47 | 0.16 | 0.57 | 0.08 | 0.24 | 0.34 | −0.23 | 0.44 |
 2019 |  | 0.53 | 0.11 | 0.68 | 0.04 | 0.18 | 0.48 | −0.20 | 0.49 |
 2020 |  | −1.55 | < 0.001 | −0.63 | 0.19 | −0.66 | 0.04 | −1.07 | 0.001 |
Model statistics | |||||||||
 α |  | 0.50 | 0.47 | 0.30 | 0.32 | ||||
 AIC |  | 3.63 | 3.60 | 3.47 | 3.50 |