In country WYZ, a professional tasked with validating quantitative models at a credit rating agency is assessing models from a credit risk analytics team. The professional observes that the rating migration matrix model relies on data spanning from 2013 to 2022. During this period, the WYZ economy experienced a minor recession and several phases of economic growth. However, in 2023, the economy is expected to face a substantial downturn, more severe than any previous economic downturn recorded.