I recommend you to read the hive whitepaper for more details.

A little excerpt:

Current Allocation & Supply: Starting with the network's 16th hard fork in December 2016, Hive began creating new tokens at a yearly inflation rate of 9.5%. The inflation rate decreases at a rate of 0.01% every 250,000 blocks, or about 0.5% per year. The inflation will continue decreasing at this pace until the overall inflation rate reaches 0.95%.
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This will take about 20.5 years from the time hardfork 16 went into effect.

https://developers.hive.io/resources/whitepaper.html

Hive on!