This D3v5 proportional symbol map, "U.S. House Sale Prices Ten Years Growth Trend" analyzes the U.S. house growth trend from March 2009 to December 2018, which is approximately a 10 year trend.
a) The user can visualize the size of each single bubble as each city's ten-year sales price difference.
b) When the user mouses over a single state, the name of the state will be shown.
c) When the user mouses over a single bubble, the bubble will show a more specific bar chart which represents that specific city's year by year sales/rental price difference. At the same time, the city name, state name where the city is at, and the ten-year house price difference of that bubble/city will be dispalyed in the top of the map.
We can learn a lot from this interactive visualization. Although if I do not look at details, I still can visualize that "San Jose" has the biggest 10 year house sales price difference among the whole U.S., when I mouse over the bubble representing "San Jose", which is the biggest bubble in CA(or the U.S.), I can see that the house sales price in the year 2010~2011 from the yearly price difference bar chart is, interestingly, decreasing.