Reference Data in Jeju 11 indicators covering reference data for Jeju. IndicatorLatest Year10-yr change Rank Cooling and heating degree days - Cities and FUAs — Cooling degree 445.78 Degree days 2025 up 159.8% 248th Cooling and heating degree days - Cities and FUAs — Change in cooling 224.91 Degree days 2025 up 556.2% 38th Cooling and heating degree days - Cities and FUAs 1,144 Degree days 2025 down 3.0% 839th Cooling and heating degree days - Cities and FUAs — Change in heating -144.51 Degree days 2025 down 32.1% 353rd Precipitation - Cities and FUAs — Extreme precipitation days 24.67 Days per year 2024 down 15.1% 122nd Precipitation - Cities and FUAs — Change in extreme precipitation 3.68 Days per year 2024 down 54.5% 264th Dependency ratio - Cities and FUAs 23.5 Percentage of population aged 15-64 years 2023 up 39.1% 910th Wind threats - Cities and FUAs — Exposure to wind threats 0 Percentage of area 2023 down 100.0% 273rd Coastal flooding - Cities and FUAs — Built-up area exposure to 0.2222 Percentage of built-up area 2022 down 49.4% 153rd Internet speed - Cities and FUAs — Downloading speed -16.2 Percentage of national value 2025 up 6.9% 1220th Internet speed - Cities and FUAs — Uploading speed -17.5 Percentage of national value 2025 down 18.2% 1013th