Few months back i purchased arround 15 to 16 btc when bitcoin price was 10000$ to 11000$ each btc but now arround 4000$ each btc .Just waiting for 11000$ for each btc than i should leave btc and i can see bitcoin have no future in this time.
You should always pay attention to your assets more often if you have that much balance. Of course the other factor is whether your goal is for longterm or short term, if you have a short term, you will lose now, if longterm, you still have another chance.
It would be better to use some to take short term profits