Update index.mdx

Author: mchaamsler

docs/c-climate-data/index.mdx

@@ -11,7 +11,7 @@ sidebar_position: 4
 | C3 | [Ground-based spatial climate data](/c-climate-data/c3-ground-based-climate-data) <br></br> Precipitation, temperature and sunshine <br></br> Daily, monthly and yearly | expected to be available in 2025 |
 | C4 | [Satellite-based spatial climate data](/c-climate-data/c4-satellite-based-climate-data) <br></br> Radiation and cloud cover <br></br> *Hourly [to be verified]*, daily, monthly and yearly | expected to be available in 2025 |
 | C5 | [Radar-based spatial climate data](/c-climate-data/c5-radar-based-climate-data) <br></br> Hail <br></br> Monthly and yearly | expected to be available in 2025 |
-| **C6** | [**Climate normals**](/c-climate-data/c6-climate-normals) <br></br> Temperature, precipitation and sunshine for normal periods 1961-1990, 1981-2010 and 1991-2020 <br></br> Monthly and yearly | **Download** via [opendata.swiss](https://opendata.swiss/dataset/klimanormwerte), as ZIP (in TXT format) |
+| **C6** | [**Climate normals**](/c-climate-data/c6-climate-normals) <br></br> Temperature, precipitation and sunshine for normal periods 1961-1990 and 1991-2020 <br></br> Monthly and yearly | **Download** via [opendata.swiss](https://opendata.swiss/dataset/klimanormwerte), as ZIP (in TXT format) |
 | **C7** | [**Spatial climate normals**](c-climate-data/c7-spatial-climate-normals) <br></br> Temperature, precipitation and sunshine with 2 km grid size for normal periods 1961-1990 and 1991-2020 <br></br> Monthly and yearly | **Service or Download** via [opendata.swiss](https://opendata.swiss/de/dataset?q=klimanormwerte&sort=score%20desc%2C%20metadata_modified%20desc&organization=bundesamt-fur-meteorologie-und-klimatologie-meteoschweiz&res_format=SERVICE), as WMS and WMTS or in NetCDF and GeoTIFF format |
 | **C8** | [**Climate scenarios**](/c-climate-data/c8-climate-scenarios) | **Download** `CH2018` via [NCCS webpage](https://www.nccs.admin.ch/nccs/en/home/climate-change-and-impacts/swiss-climate-change-scenarios.html) <br></br> [`CH2025`](https://www.meteoswiss.admin.ch/about-us/research-and-cooperation/projects/2023/climate-ch2025.html) expected to be available in November 2025 |
 | **C9** | [**Spatial climate scenarios**](/c-climate-data/c9-spatial-climate-scenarios) | **Download** `CH2018` via [NCCS webpage](https://www.nccs.admin.ch/nccs/en/home/climate-change-and-impacts/swiss-climate-change-scenarios.html) <br></br> [`CH2025`](https://www.meteoswiss.admin.ch/about-us/research-and-cooperation/projects/2023/climate-ch2025.html) expected to be available in November 2025 |