This APR calculation is a result of VOLT emission earned by LPs for providing liquidity to the pool
MTRG/BUSD liquidity provided - The current prices of tokens are used to determine the APR
VOLT Emission earned - The current price of VOLT is used to determine the APR
The APR range is result of potential boost in VOLT earnings based on the veVOLT NFT attached to the Liquidity. Liquidity providers can boost up to 2.5x their VOLT emission when veVOLT locked by the LP is in same proportion of the liquidity provided by the user in the pool.
In screenshot above:
10% APR (Min APR) - No veVOLT locked on Voltswap
25% APR (Max APR) - veVOLT locked on Voltswap in proportion to the liquidity provided
Note: Liquidity Providers have to lock LP tokens in the gauge to earn VOLT emissions