I agree with you, maybe this could help the author: http://bost.ocks.org/mike/constancy/

this is cool, will check it out tonight

I came here to say the same thing. Having one section morph into another is unnecessarily confusing, and mostly masks the entire point. Also, it would be nice to slice this data across time as well, by clicking on a particular box and viewing a plot below the main visualization.

yes! this is how it already works! if you click a box, it will show you a graph of how that item has changed over time. If you double click, it will create a new treemap made up of the underlying data for that box.

I don't think that's all that wrong since you are moving from one budget to another, but what confuses me is that the animations are not consistent. Although they seem to be fixed to the specific display state it's inconsistent. But I do like the replacing effect of the transitions to not simply change the labels and numbers which is not easily noticed.

this is because some blocks are added and removed from year to year. In this type of visualization, it's impossible to keep things the same size and position while also changing the amounts.

The best way to use this isn't to switch between years. If you click on any cell, you can see a graph of how that changes over time. If you double click on any of the cells, you can see a new visualization of everything that makes up that cell. For example, double clicking on the department of justice will show you it is made up of X billion from the department of prisons and X billion from the FBI.

It's definitely not because some blocks are added and removed. Click on the same year twice and the blocks animate all over the place. The animations are worse than useless -- they actually hinder the ability to compare two years.

No I think what he meant is why the "Defense--Military Programs" is not the same rectangle (with changing size/pos) between budgets.

maybe a Google Motion Chart like the Hans Rosling charts would be an interesting visualization to solve for that effect. https://developers.google.com/chart/interactive/docs/gallery...