Formula to Determine NAV Recovery Period

Personal finance
1

If NAV of my debt fund is growing at constant rate, how much time it will take to reclaim the same NAV after a sudden drop of x%? Is there any mathematical formula to calculate this? Got below answer from Google Bard, but not sure, if it is correct.

Time = (1 + x%) / (Growth rate) - 1

Derivation:
NAV = Initial NAV * (1 + Growth rate) ^ Time
(NAV / Initial NAV) = (1 + Growth rate) ^ Time
Time = log((NAV / Initial NAV)) / log(1 + Growth rate)
Time = (1 + x%) / (Growth rate) - 1

2

not sure about the above one but you can try this:
b = log a (c)

where b = time, which you will get in decimal years.
a= log base = (1+growth rate)
(c) = (1/(1-x% drop))

3

till here you will get your value, the last line of your formula seems to be wrong