XONE is part of BondBloxxs suite of duration-specific US Treasury ETFs. Starting with the constituents of the funds parent indices, the portfolio is constructed using two duration buckets of US Treasury securities: 6-to-12-month duration securities from the Bloomberg US Short Treasury Index and 12-to-18-month duration securities from the Bloomberg US Treasury Index. These two buckets are blended according to a weighting scheme required to achieve a target average portfolio duration of one year.