Process Step, Elapsed Time & Volume diagram

I'm trying to make a graph which shows each of 5 steps in a process, with a horizontal line the width of the elapsed time for that step, and with a vertical position for the volume of items in that process step.
I'm visualising something like a waterfall diagram, stepping down from left to right with varying widths of lines according to the time for that step.
Happy to consider other layouts if it articulates the decreasing/increasing volume in each step along with the time each step takes.
3 series of the same steps for different teams following the same process, with differing volumes and differing times for each step.

Any advice appreciated

Hello DimmiD and Welcome to Excel Forum.
Perhaps something similar to the attached Gantt chart would do what you want.
The formula for populating the step numbers in the chart is: =IF(AND(COLUMNS($F2:F2)>=$B2,COLUMNS($F2:F2)<=$C2),$A2,"")
The conditional formatting rule is: =F2<>""
For future reference, you will usually get quicker responses if you include a sample file (instructions are given in the banner at the top of the page).
Let us know if you have any questions.

You could try free Gantt chart template by Microsoft.
Open Excel > New file > Search for Gantt Chart > select the template from list.