This hat needs a raise, due to the gradual rise in price. This was caused by everyday traders buying low, selling high, and the process kept repeating until the price was higher than it originally was.

Sale #1:

Sold by quicksell bot for 16, bought by this guy:

https://backpack.tf/profiles/76561198371165861#!/compare/1581033600/1581206400

Sale #2:

Sold to the person currently possessing the unusual for 8k pure, plus a heavy unusual with buy orders of 8k, 8+8=16k

https://backpack.tf/profiles/76561198080425549#!/compare/1580860800/1580947200