I don't use Betfair and if I understand correctly:
On Betfair site are betting on what will be the bitcoin price on December 31st?
Predicting the price of bitcoin is very difficult and if Betfair is offering this opportunity to bet on what the bitcoin price will be by on December 31st, then Betfair should offer an odd of at least 2.20. This would be more rewarding since predicting the bitcoin price is very difficult, of course I also agree that every single day the value of the odd should be reducing.
Very nice odds, all serious predictions from experienced traders predict a price between 6.5k to 8.5k.
That's free money for me. I bet 3 digits on this.
the price is at $7200, I believe it is not free money because there is a high risk of falling below $6500 before December 31, and don't believe these " experienced traders " because they always fail their predictions