I really want to know which alt you mean because I believe most altcoins will follow the bitcoin price trend so far. IMO, the current average of the top altcoins have fallen by more than 80% since their last ATH, I can expand the list here for comparison.
The following is the current market condition regarding the percentage decline in bitcoin prices and top altcoins after last year's bitcoin ATH.
Bitcoin - [-71.3%]
Ethereum - [-78%]
BNB - [-69.5%]
Cardano - [-84.9%]
XRP - [-90.6%]
SOLANA - [-87.1%]
Polkadot - [-86.6%]
TRON - [-73.7%]
LEO - [-36.5%]
Shiba Inu - [-90.6%]
Yeah, I was about to say that, You can also add Doge on it as per coinmarketcap:
All Time High
May 08, 2021 (a year ago) $0.7376
92.10%
So majority dump way more than
BTC. So regardless of the liquidity argument, lol, they are altcoins, well still very difficult to conclude. So it could be a plus/minus for measurements, but we also have to factor volatility in my opinion.