That being the case, you'll NOT want to use Dual-Axis. You'll want to use Map Marks Layering which gives more independent control over how you want to display your results: You can then 'Hide' the null values Which gives you: Best, Don Wise - Please don’t forget to ...
If you're using 2021.4 or later, you can use the multi-data source layering and add in a set of country polygons and turn those white as your 'background.' I like the files from Natural Earth: https://www.naturalearthdata.com/downloads/ -Sarah Tableau Research Expand Post UpvoteReply ...