40%-50% of people in the Earth were owned bitcoin by 2020. Because most of the people were still scared to scammed, they always thinking that online or digital transaction were scam especially to the old one. But I'm still hoping that most of the people in the Earth were accept the value of bitcoin.
if my calculation is right. maybe only 1% of whole earth population using bitcoin right now. so don't expect for 40 to 50% using bitcoin.
if 5% of whole world use bitcoin by 2020 it would be a very big achievement.
as you said lots of people already scared of bitcoin.