Did PFD compared to Effectives totals change during the course of the war?


Jan 30, 2020
Have read a great deal recently about various attempts to compare Union and Confederate regimental, brigade and divisional totals and hoping to achieve more realistic comparable totals. One of the difficulties is that both sides had different ways of recording numbers. One of the most talked about discrepancies is the difference between present for duty figures and effectives i.e. the numbers engaged in battle.
I was wondering how did these totals compare and did the difference between them vary from year to year or campaign to campaign?
Perhaps the starkest difference would be during the Maryland Campaign particularly on the Confederate side. I would assume that the difference between the two totals would be considerably larger than say during the Gettysburg campaign or Overland campaign but is this correct? if so how do these numbers compare from each campaign or year?


Feb 18, 2017
The Maryland campaign sees a particularly large amount of straggling, which is why the PFD/Effectives ratio is different. Typically it would be around 83% of PFD as Effectives but in the Maryland Campaign it's more like 63-66%.

Aside from this incident it would be most notable when one side was suffering majorly from straggling or "hard hit", or where one side was at the end of their logistical tether. However over the course of the war both sides did transition to using numbers closer to effectives (for example IIRC it was Burnside or Hooker who moved the logistics out of the PFD column on the returns for the Army of the Potomac) and so later on in the war both sides tend to be using something closer to comparable figures.

There were cases where people who didn't quite track with how there were different categories thought one general or another was "manipulating" numbers, and this sometimes had an impact, but aside from that it's mostly how each side prefers to count their own troops. It may have affected Meade's behaviour at Gettysburg that he thought he was facing an enemy with more men than him (per the BMI) but it's hard to see how it would make him make a false disposition.