Excel built-in histogram tool only allows equal bin-width. We must create instead a "variable width column chart" as explained by Jon Peltier. This can be a tedious and error-prone process if you've got a lot of bins. Video tutorial for Excel 2016. The main steps are as followed:
- Create a cascade table:
![Input table](https://i.stack.imgur.com/rjwsi.png)
should turn into:
![Cascade table](https://i.stack.imgur.com/dchfR.png)
Note: dummy + Label columns aren't required, but help with labeling
- generates a stacked area chart (a type of Area chart)
![stacked area chart](https://i.stack.imgur.com/PRZlI.png)
- Then change the Primary Axis's category to Time-Scale to straighten the areas into bars. As explained by Jon Peltier, this is because:
This is somewhat misleading, as Excel time-scale axes only consider dates and ignore times.
![straightened columns](https://i.stack.imgur.com/EiMHW.png)