Hi, I am trying to get a simple formula to calculate a ballpark cost for a 2/5 flattener. Could you guys take a quick look to see if this is ok? My formula is Roll down = 4*(5yield-4yield) â (5/2)*1*(2yield-1yield) Carry = 5yield-(5/2)*2yield [5yield means 5 year treasury yield and same for others] Then I sum up the two. I just need to get an approximate number assuming YC doesn't change for a year. Are the formulas correct?