Data does not show much in this state. Let's group data points by Country. Scroll to color the groups.

The patterns emerge now. Let's connect the dots to see the patterns better

Hover over to activate horizontal tooltip lines.

Let's have a look at the underlying voronoi cells which enables to highlight closest point to current mouse position. This allows tooltips without user being exactly on the data point itself.

Voronoi partitions the space into polygons containing the closest points to each point other than any other point.

Now, hover over your mouse over the voronoi cells to see activation of the tooltip lines and points closest to your mouse.

Let's hide the voronoi cells.

And the chart is now ready.