So you'd like to plot the length of time in service by other metric, correct? What is the 2nd metric?
I would use x,y charts in Excel. Time in Service would be on the bottom axis, I'm not sure what you'd have listed for your other axis, and then the dots would represent injuries. You could add multiple series per department so that different departments were different colors.
Key things to remember:
-Sort your table by Dept (whatever you want your different series to be) - You'll have to manually add each set of x,y through click n drag
-The Excel wizard sucks with Scatter charts. Immediately after creating it via Insert-> Scatter... right click, edit series and delete the series that are there. Add your own manually.
-Excel doesn't let you label the dots. So if your colors were departments but you wanted a label for the employee's name, you can't do that without doing it manually. There's a free add-in that will automate that task, called XY Chart Labeler
There is a rather expensive but neat tool call Tableau that works well for this sort of visualization.
If you want to create complex combinations of a variety of factors on multiple scatterplots, the free statistics program R can do it. There's a huge learning curve and it's frustrating to pick up - but when you get it it's a big time saver if you have 10 variables which all need compared to each other (100 scatterplots!)
