| 2011 | 2014 | 2017 | 2020 |
---|---|---|---|---|
Low-income (%) | Â | Â | Â | Â |
 SII (95% CI) | 2.334**(1.805—2.862) | 1.981**(1.401—2.560) | 2.217**(1.447—2.807) | 2.097**(1.590—2.605) |
 RII (95% CI) | 1.055**(1.044—1.067) | 1.054**(1.040—1.069) | 1.060**(1.045—1.074) | 1.057**(1.044—1.081) |
Education (%) | Â | Â | Â | Â |
 SII (95% CI) | -2.495**(-3.045– -1.945) | -2.664**(-3.323—-2.005) | -2.327**(-2.888—-1.647) | -2.866**(-3.400—-2.331) |
 RII (95% CI) | 0.933**(0.922—0.945) | 0.933**(0.920—0.946) | 0.935**(0.922—0.947) | 0.919**(0.908—0.931) |
Tax payment | Â | Â | Â | Â |
 SII (95% CI) | -2.035**(-2.682— -1.389) | -1.003*(-1.908— -0.099) | -1.189**(-2.072 — -0.307) | -2.031**(-3.163 — -0.899) |
 RII (95% CI) | 0.944**(0.930–0.958) | 0.971*(0.951–0.991) | 0.964**(0.943–0.986) | 0.926**(0.899–0.954) |