Personally, I believe the ideal approach is to increase the APR when the price of HIVE is low and decrease it when the price of HIVE rises.
For example: 1,000,000 HIVE = 185,228 HBD at the current price, but if the price rises to $0.5, HIVE could only pay out 370,456 HIVE instead of 1 million HIVE, provided that the price doesn't stay low for too long. This is because around 200,000 HIVE is paid out annually in APR at 20%.
Some people believe that it's unfair for the APR of HBD to be higher than that of HIVE POWER and that HBD holders only sell. Currently, it's possible to earn an average of 11% to 12% APR on HIVE POWER, assuming the price doesn't drop. Active participants can increase their profits by having more HIVE POWER, as it tends to attract more votes the larger you are in the network. The advantage of HIVE POWER is that you have a governance vote and can dictate the direction of the HIVE blockchain.
Others believe that the APR of HBD hinders the attraction of investors to other projects on HIVE-ENGINE.
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