Averaging raster values within a vector area

[SaraJL]

Hello everyone!

I'm working on a example project and I'm stuck on a specific step - I have a raster layer of index values and I need to figure out the average of those values within the borders of a region. 

So this case - I have regions in Japan and I'm trying to figure out the average Satoyama Index. The index values are a raster layer and the regions are vector borders. 

Any ideas on the best way to approach it? I attached a screenshot of what I have so far.

Any advice is welcome! Thank you for the help!

Sara

[DanPatterson]

I would start by examining the zonal tools

Zonal Statistics (Spatial Analyst)—ArcGIS Pro | Documentation

Zonal Statistics as Table (Spatial Analyst)—ArcGIS Pro | Documentation

How the zonal statistics tools work—ArcGIS Pro | Documentation

details are in the links