I have a CFA with the following coefficients: chisq,scaled = 101.791, df = 84, baseline,chisq,scaled = 1525.369. If I simply use the scaled results in the usual formula to calculate the IFI, then I get: (1525.369 - 101.791) / (1525.369 - 84) = 0.988. This also corresponds approximately to the result that EQS produces. Lavaan calculates the following result: ifi,scaled = 0.933. How does this not insignificant difference arise?