It's indeed not perfect on this front. Furthermore, real statistician pointed that a continuous line for the pyramid was not the good choice, but I was looking

It's indeed not perfect on this front. Furthermore, real statistician pointed that a continuous line for the pyramid was not the good choice, but I was looking more for interesting visuals and ways to spark the interest of people. That's why I used these animations, it gives the feeling to people to see what's happening. Unfortunately, the way I animate this graph is very basic and I did not take time to make it perfect (the data crunching, SEO optimization and UI fine tunings already took way more time than I wanted to put in this). This is just a hobby project for me.