{"entity":{"iso2":"TO","iso3":"TON","name":"Tonga","slug":"tonga"},"indicator":{"licence":"CC BY 4.0 (Our World in Data)","slug":"ipv1-number-unvaccinated","source":"WHO & UNICEF (2025); UN, World Population Prospects (2024) \u2013 processed by Our World in Data","source_url":"https://ourworldindata.org/grapher/ipv1-number-unvaccinated","title":"Number of one-year-olds who have not received the inactivated polio vaccine","unit":"one-year-olds"},"observations":[{"date":"2015-01-01","value":1792.56},{"date":"2016-01-01","value":107.68},{"date":"2017-01-01","value":25.99},{"date":"2018-01-01","value":24.98},{"date":"2019-01-01","value":24.33},{"date":"2020-01-01","value":23.81},{"date":"2021-01-01","value":23.6},{"date":"2022-01-01","value":23.84},{"date":"2023-01-01","value":23.98}],"summary":{"latest_period":"2023-01-01","latest_value":23.98,"max":1792.56,"mean":230.086,"min":23.6,"of":194,"rank":183,"trend":"volatile"}}