Sorry I've been much more sparse on the forum lately, just trying to spend less time online and more time getting some projects done!
But, I've been diligently wardrobe tracking for 2 years. Will not be continuing it, as I think I learned what I needed, and it will inform my purchases going forward. My tracking was paper and pencil, and included all wardrobe items (inc sleep wear this wear) and cost. Purchases have been approximately one in- one out, with a slight reduction overall.
That said: my needs change a lot year to year. In 2020, when I was WFH, I wore gear most days. When I worked in office more before that, I wore heels much more than now. 2023 we had a mild winter, and my sandal booties, short sleeves, and thin pants were worn often, this winter has been much colder. I really do need a range of things, but generally not many similar things.
Worn/used a lot: sleepwear, black tops for all seasons, larger bags, Birkenstocks, most of my pants and summer maxi skirts (keep to about 10 each) wool coat, leather jacket, thin puffer, swimwear, low heeled booties, black blazer, black cardigan. All of these things I can replace as needed next year.
Not worn much: cycling gear (swam instead), heeled sandals (I don't work in office in summer), cold weather skirts (hate tights, reach for pants instead), dresses (need more exact fit than seperates), tall boots (due to not wearing skirts/dresses in winter), small bags (don't fit planner, water bottle,;etc), scarves/necklaces, deep winter wear (heavy coat, hats, snowboots), and more expensive (except shoes) and dressier things.
Next year, I will (I mean it this time!) do a French 5 Piece, for everything that got under 20 wears in 2 years. Though my wardrobe isn't that big, I have very limited space, and want to be sure I don't give that space (and $) to lots of low use items.
I do recommend tracking, and will do it again if my life changes a lot, but don't feel the need to continue next year- except possibly the few benchwarmers (under 10 wears).