| Year | The proportion of elderly population | Year | The proportion of elderly population | Year | The proportion of elderly population |
| 2010 | 6.4 | 2015 | 7.1 | 2020 | 7.9 |
| 2011 | 6.5 | 2016 | 7.3 | 2021 | 8.1 |
| 2012 | 6.7 | 2017 | 7.5 | 2022 | 8.3 |
| 2013 | 6.9 | 2018 | 7.6 |
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| 2014 | 7.0 | 2019 | 7.7 |
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