Filing FBAR and Form 8938

So recently after about 20 years I started looking at my financial assets in my home country. I had invested a very moderate sum of money(less than $10k ) 20 years ago via some financial advisors in some mutual funds and stocks. My home country had strict requirements to access those accounts so for the most part my login and any information about how those stocks were doing were all unknown to me. As I worked to unfreeze my brokerage accounts in my home country, I realized that some mutual funds etc. had given me 3500% return. My stock portfolio had ballooned into a fairly substantial amount (more than $50k). Which means I have to file for FBar and Form 8938 but I don't know for how many years I have to file going back because I don't know like what my net asset value was in all those years. Should I just start filing from this year? If I file for the previous years I don't even know what the asset values were for those years