Well, this is pretty dead but I hope at least a few people still use it as it is a great little feature. As I mentioned above, one has to be aware that the report is rounded down, so "+$1M" could actually be hiding pretty much half of a profit of $1,999,999 or actually be a profit of $1M exactly. It is generally not a problem when manufacturing for up to +$1M, since thousands grow quickly and hundreds are largely irrelevant, but at that turning point of a million, you end up losing a lot of information. Am I producing for +$1.005M or +$1.8M?
So I bring you: My first code contribution to OpenXCom, albeit a tiny one that modifies something that modifies OpenXCom. As you can see in the screenshots below, if your profit is less than 10 thousands/millions/billions, the display will change from +$X to +$X.Y, so you have a bit better idea of what is happening. Like the original, numbers are rounded down, so if it displays +$1.2M, you could be making 1.2 or 1.299,999 millions, but tens of thousands aren't that big a deal here. This keeps the error of the estimate under 9%, instead of under 99%.
The changes are in the patch file. Just type "git am < Patch_MonthlyMfgProfit3.patch" in your git repository (or do whatever your git gui asks for to patch). It is not changing much, so you can also just go in the code to apply them yourself. Not that this modifies what Myk002 did and requires it. It is not a stand-alone feature.