How long does getting dressed actually take you?

Trying to plan an evening and I have realised I have no idea how much time to leave for actually getting dressed.

Last time I did a top and leggings and it took me about forty minutes, which included a great deal of stopping to reposition things and one moment where I nearly panicked about a sleeve. I do not know whether that is normal for someone with three months of practice or whether I am unusually slow.

How long do people actually take? And does it drop a lot with experience, or is this just a thing you have to build into the evening forever?