https://etherscan.io/address/0xf302f9f50958c5593770fdf4d4812309ff77414f#readContract

This is the token admin contract. You can see the emission rate (getInflationRate = 0.239 BAL/second = 145k BAL/week)

And the RATE_REDUCTION_COEFFICIENT 1.189 = 2^(1/4) This is applied to the inflation rate every year so as to achieve the emission scheduled approved by governance