xSUSHI is a yield-accruing token, backed by SUSHI tokens. It was created as a means to lock SUSHI tokens and to get a share of all the Protocol revenue. xSUSHI is minted by locking SUSHI in SushiBar.
When users make trades on the SushiSwap DEX a 0.3% fee is charged. 0.05% of this fee is added to the SushiBar pool in the form of LP tokens. Atleast once every day, all the LP tokens are sold for Sushi on SushiSwap DEX. The newly purchased Sushi is then divided up proportionally between all of the xSUSHI holders in the pool, meaning their xSUSHI is now worth more SUSHI. Because of the way the rewards are generated, the price of xSUSHI will increase with the value of SUSHI, and the value of one xSUSHI will always be greater than the value of one SUSHI.
How does xSUSHI and SUSHI relate interms of supply ? xSUSHI is staked SUSHI. Hence a proxy to amount of SUSHI locked within the ecosystem.
60 Million xSUSHI tokens are in circulation. This means, there is atleast 60 Million SUSHI tokens staked, which is 25% of the total supply. Over the past 3 months, the amount of xSUSHI hasn't changed alot, suggesting that most SUSHI and xSUSHI holders are HODLing and are bullish on Sushiswap DEX.
All data for this chart was take from Flipside's curated ethereum.erc20_balances
table.