I have about 20 pair of knickers. I know I need to replace some, but am still missing BHS,where I used to purchase them. Some newer ones came from Sainsbury , but so miss BHS for this sort of thing.
Socks, I only wear in the winter months, autumn and spring I use ankle high stocking type things, and - as soon as it gets warmer and I am able to wear skirts and sandals I do not wear anything else on my feet.
However, I have a lot of socks as I do like to match the colour of them to the trousers and jumper I am wearing, so probably about 30 plus pairs.
I only do washing once a week, so never come close to running out of clean knickers and socks.