I dont!
You should charge what the quality of the work is worth...or rather, I should say, what the quality of the work commands.
I don't know anyone (who I would take seriously) that would not need to colour correct (WB) and density correct the vast majority of the the files they had shot at a wedding whether they had shot RAW or jpg, if they wanted the client to see the true quality of the work, shot.
You should have realised this and taken it into account before you took on the job. If the quality of what you have produced is not such that it cannot command a fee worth doing all the work for in the first place, perhaps you have chosen the wrong job.
I repeat, the fee the work can command (and get bookings) will be based on how good it is, not how many there are.
Typically, I shoot around 700-800 shots on a wedding and cull them down to 300-400. My culling process is, If I think that the shot is good, it stays, if there are more than one good shot of a similar thing only the best one stays, unless there is a point to having a sequence, (walking up the isle, confetti, etc).
Occasionally, on long jobs (like 10 hours) I will shoot more than I said above, here is one where I shot just under 1400 images and once culled, using the procedure above, I still presented the client with over 750 images.
They were thrilled with the work (and apparently, so where the magazines that want to use some of the shots) and there was never a hint of the fact that they felt there were too many images or or there was any dross in what was previewed to them.
Here is the wedding, (it could take ages to download though)
http://www.johnprendergastphotography.co.uk/cam_adobe/index.htm
If you were the client, would you feel that there was a significant percentage of the shots in that set of previews that shouldn't of made it through to being left in?
That is a rhetorical question bye the way. I have alot of experience in knowing what to keep with a view to what to have the client choose from.
I suppose, the point of my reply is...the OP is now finding out what Wedding Photography really is and he and others are finding out the hard way, if they are really cut out for it or capable of it in the first place.
P.S. That wedding I have shown took about 4 hours tops to edit and process from shooting RAW to the quality that is hinted at in the above link and that is including producing full res jpgs, DVD playable slide shows with audio soundtracks, etc, etc, etc. so I don't know how it is taking anyone 3 or four days to do it.
What are you doing that takes that long??