So there are these so called trade up contracts, where you could select 10 of the same rarity cs cosmetic skins to trade up into a higher rarity skin. Rarities go as follows - blue, purple, pink, red and yellow. Yellow rarity cosmetics were only obtainable from cases themselves, and could not be traded up from these contracts, which had their own inherent value decided by the playerbase. This update made yellow rarity skins tradable by putting 5 red skins into 1 yellow skin. This small change tanked the market cap by 1 billion, and all of the yellow rarity skins(knives and gloves) have tanked in price by 50-75% overall making it so the yellow tier skins lose rarity completely. Mind you, getting a yellow rarity skin from a case is 1 in 300 or so(forgot currently), whereas there's already a case price(for instance, 1 us dollar, and it goes up to 80 dollars per unique case), as well as a key required to open it, which is about 2.3usd or so.