Merge pull request #4252 from pullhub/explore-sdmx

Add topics/sdmx/index.md for SDMX

Author: tomthorogood

topics/sdmx/index.md

@@ -0,0 +1,10 @@
+---
+display_name: SDMX
+related: statistics, open-data, data-science
+short_description: SDMX is a global initiative and ISO standard to improve Statistical Data and Metadata eXchange.
+topic: sdmx
+url: https://sdmx.org/
+wikipedia_url: https://en.wikipedia.org/wiki/SDMX
+---
+SDMX (Statistical Data and Metadata eXchange) is a standardized framework for sharing statistical data and metadata. Developed by national statistical agencies, central banks, and international organizations, SDMX enables seamless exchange of structured data across systems. It encompasses RESTful web services, XML (SDMX-ML), JSON (SDMX-JSON), and CSV formats.
+