There is a general consensus that bud looses 80% of it's weight when drying.
Personally, I find it to be higher.
I have not weighed individual buds. I have done it by the box. Which gives a better spread of the type of buds weighed. However, they are all on twigs to enable hanging, but off the twig for the final weigh in. 90% losses. As high as 93% when no RH meter was used. I have done this many times, though not since using RH as a guide. Which has led to heavier buds I'm sure.
Some pics here show strings put back'n'forth in tents, to hang from. I did similar but my strings are back n forth within a cardboard box. Typical sized boxes, like 30x30x40 so no entire frames being hung. 250mm 'trimming sized' bits at most, and just as many bits a couple of inches long. Roughly 5oz per box dried. This is a nice method for a few reasons, one being, you can weigh it.
Fairly soon I will be chopping 'trimming sized' bits off, trimming, and laying them in mushroom trays. This will give me chance to do a more modern weigh in.
I like shroom boxes/crates. It's a bit like hanging nets, but free from your local curry takeaway. They are designed to stack shrooms without keeping any damp in. I like to half fill them, but have got near the top before. Which is fine, as a day later it's half the size. I just stick um in the then empty veg tent, with a circulatory fan and extract set with an RH controller.
Methods like this allow bulk weighing, to assess what is going on. If that's what you want to do.
I will suck a lot of water out early on, with low RH, but not enough to dry the outer leaves. I want everything at 60% and never below, but see no gain in waiting to get there. It's days at and above 60% that count. Days at 70 don't count for any more than days at 60. It's just an extra day risking mould. So I get it down as quick as I can, without the outsides dipping below 60 from trying too hard.
I hope that's all relevant