A great question. I would say 10% or lower would be a suitable level, but the return should be less than the return from Hive Power. HBD understates the current Hive inflation that is officially 70k Hive per day, but we have an increasing inflated HBD which is a hidden inflation of 37,859,926 Hive! This may be only 10% of the supply but seems to have created enough sell pressure on Hive to stall the price very well.