Reference Data in Jena 15 indicators covering reference data for Jena. IndicatorLatest Year10-yr change Rank Cooling and heating degree days - Cities and FUAs — Cooling degree 21.98 Degree days 2025 down 77.4% 945th Cooling and heating degree days - Cities and FUAs — Change in cooling -22.22 Degree days 2025 down 141.8% 899th Cooling and heating degree days - Cities and FUAs 2,194 Degree days 2025 down 3.7% 305th Cooling and heating degree days - Cities and FUAs — Change in heating -447.78 Degree days 2025 down 23.4% 958th Cooling and heating degree days - Cities and FUAs — Change in heating 7.59 % change on previous year 2025 down 75.5% 399th Cooling and heating degree days - Cities and FUAs, annual growth rate 1.71 % change on previous year 2025 down 77.8% 377th Cooling and heating degree days - Cities and FUAs — Change in cooling -161.64 % change on previous year 2025 down 119.3% 844th Cooling and heating degree days - Cities and FUAs — Cooling degree -72.61 % change on previous year 2025 down 144.5% 996th Precipitation - Cities and FUAs — Extreme precipitation days 1.67 Days per year 2024 down 74.4% 1158th Precipitation - Cities and FUAs — Change in extreme precipitation -0.384 Days per year 2024 down 108.6% 946th Dependency ratio - Cities and FUAs 35.4 Percentage of population aged 15-64 years 2025 up 15.7% 311th Wind threats - Cities and FUAs — Exposure to wind threats 0 Percentage of area 2023 — 271st Coastal flooding - Cities and FUAs — Built-up area exposure to 0 Percentage of built-up area 2022 — 277th Internet speed - Cities and FUAs — Downloading speed -5.9 Percentage of national value 2025 up 43.8% 1056th Internet speed - Cities and FUAs — Uploading speed -13.1 Percentage of national value 2025 down 142.6% 945th