The risk-free value, which is the amount of money that the Treasury guarantees to back XPH. The risk-free value comes from the assets in the liquidity pool. The Protocol considers XPH and BUSD to be equal because we measure XPH by its intrinsic value. This means that we only need to care about the sum of the assets in the pool, not their value. According to the constant product formula x y = k, the risk-free value is the minimum of x + y, which happens to be when x = y. We can use the square root of x y to determine this. When bonds are sold, the balance of stable coins in the treasury increases. The RFV is calculated differently for different types of bonds. For securities purchased with BUSD, the calculation is as follows: