It's definitely sustainable
It goes through a pattern of rising 35-40
Dropping 20 going up 40 (cents).

I invested today cause I'm 200% sure steem is steadily making a clime ratio higher than its dip
It'll become exponential growth in a year or so.
Steemit will overtake fb and YouTube. The future is humans constantly on their phones, humans love writing or expressing themselves and they love getting paid to it.