I'm posting on behalf of a member organisation with 1,000 members, mainly in the United Kingdom but also internationally. I have exported the home post code of all members to CSV, and used it to create a Google MyMaps map, with a dot for each member's post code. I want to embed this map on our public website, because when people see how many members there are, it might encourage more to join.
However there are privacy concerns, and I have sought advice from ICO (the GDPR regulator in the UK) that it might fall below our members' expectations, because there are some post codes in rural areas where there are only a few houses, therefore this could potentially count as "personally identifiable information".
Therefore I've been looking at various options. First is a heat map, rather than dots. However, from this it will be difficult to say just how many members there are.
Second option is to remove the last two letters of the post code, i.e. "L31 5" rather than "L31 5AA", which would show the dots in a more general position. However since our members tend to be focused in specific regions of the country, this would greatly reduce the number of dots on the map, therefore defeating the object somewhat.
Another option I've heard is limiting the zoom level of the map, to stop being able to see buildings for example. This is the best option I've heard so far, but I'm not sure if it's possible with Google MyMaps. I've seen that this is possible with the Google Maps API, which I've been trying out, but I don't think it's possible to import a CSV into this in the same was as you can with Google MyMaps.
Or is there another option altogether?