Reference Data in Heerlen 11 indicators covering reference data for Heerlen. IndicatorLatest Year10-yr change Rank Cooling and heating degree days - Cities and FUAs — Cooling degree 40.09 Degree days 2025 down 41.9% 813th Cooling and heating degree days - Cities and FUAs — Change in cooling -2.31 Degree days 2025 down 108.7% 520th Cooling and heating degree days - Cities and FUAs 1,718 Degree days 2025 down 11.1% 552nd Cooling and heating degree days - Cities and FUAs — Change in heating -468.7 Degree days 2025 down 84.8% 1015th Precipitation - Cities and FUAs — Extreme precipitation days 3 Days per year 2024 down 25.0% 960th Precipitation - Cities and FUAs — Change in extreme precipitation 1.16 Days per year 2024 down 46.2% 631st Dependency ratio - Cities and FUAs 42.7 Percentage of population aged 15-64 years 2025 up 29.0% 114th Wind threats - Cities and FUAs — Exposure to wind threats 0 Percentage of area 2023 — 273rd 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 4.4 Percentage of national value 2025 up 131.6% 713th Internet speed - Cities and FUAs — Uploading speed -15.2 Percentage of national value 2025 up 56.2% 981st