Hey jerry0,

the apy for USDN is changing daily but for the last year it was constantly around 8-12 percent.

USDN is backed by waves. So if you buy USDN from the waves.exchange for example via Kredit card. Your found are used to buy Waves. Backing your USDN with Waves.

In the background those Waves are than staked.

In the past people bougth USDN and the waves price was still cheaper than today. Therefore we get an over collateralisation (Statistics for USDN can be checked here: https://dev.pywaves.org/usdn).

Normally you would receive 6% via new created tokens in waves for staking waves, but due to the over collateralisation you have more waves staked than the value of one USDN and therefore you will also become a higher yield.

If over collateralisation would stop in future you could also get a lower yield. I'am not sure about the exact algorithmyc details. But that are the main principles.