My Original X P1 Was 2007. Results in $68.6 for Y in 2025. Preferred Funding was both RMBS and CMBS. The accumulation curve should flatten out because the CMBS(not modeled). Please try 2007 for X1 to check the math. I also achieved the same result of $51.2 for Y using 2008 as the starting point like you. Accumulation is 2.35X by changing the starting point to 2008 from 2007. Thanks for your response. Ron