Drawdown
A drawdown in a trading account is the percent difference between the highest point and the lowest point of account equity during some time period.
For example, say in 2020, your account value peaks at $10,000, before dropping down to the lowest point of $5,000, before going back up again, you'd have a drawdown of 50% ($5,000/$10,000).
Drawdowns are a natural part of trading for even the best and most experienced traders.