The "return formula" in the cryptocurrency circle:
If the price drops by 10%, it will return to its original cost if it rises by 11.1%.
If the price drops by 20%, it will return to its original cost if it rises by 25%.
If the price drops by 30%, it will return to its original cost if it rises by 42.8%.
If the price drops by 40%, it will return to its original cost if it rises by 66.7%.
If the price drops by 50%, it will return to its original cost if it rises by 100%.