Data: https://gist.github.com/Junying-Li/72ef4641efd6b4abf371f5d9f4267a56

Iterated from one menu version.

What's new?

1. Changed buttons to two drop down menu.
2. Update visualizations by different start year and end year.
3. Added legend for world map.
4. Scale linear richter(radius of circles on map).
5. Added tooltips for world map.

Bar plot:

X-axis: region that earthquake occured.

Y-axis: Deaths in earthquake.

World map:

Circle: positions where earthquake occured.

Radius: richter of earthquake.

The bar plot shows the deaths caused by earchquakes in mutiple regions in different period of 19 century. The world map shows the positions where earthquakes occured and how strong they were (richter scale).