In Olgivie II, the WCAB explained that:

"[T]he DFEC rebuttal approach that is consonant with section 4660 and the RAND data to which itrefers consists, in essence, of: (1) obtaining two sets of wage data (one for the injured employee and one for similarly situated employees), generally through the Employment Development Department (EDD); (2) doing some simple mathematical calculations with that wage data to determine the injured employee's individualized proportional earnings loss; (3) dividing the employee's whole person impairment by the proportional earnings loss to obtain a ratio; and (4) seeing if the  ratio falls within certain ranges of ratios in Table A of the 2005 Schedule. If it does, the determination of the employee's DFEC adjustment factor is simple and relates back to the Schedule. If it does not, then a non-complex formula is used to perform a few additional calculations to determine an individualized DFEC adjustment factor." 

In Ogilvie II, while affirming its earlier decision in Ogilvie I, the WCAB emphasized that "the burden of rebutting a scheduled permanent disability rating rests with the party disputing that rating," "[a]ny evidence presented to support a proposed individualized DFEC adjustment factor must constitute substantial evidence upon which the Workers' Compensation Appeals Board (WCAB) may rely" and that "even if  this rebuttal evidence is legally substantial, the WCAB, as the trier-of-fact may still determine that the evidence does not overcome the DFEC adjustment factor component of the scheduled permanent disability rating."

Consistent with Olgivie II, several recent panel cases have seemed to indicate that even where, for example, the applicant provides uncontested evidence that he lost all of his earning capacity, the analysis, at least as far the WCJ is concerned, does not end there.

In Ogilvie I the WCAB stated:

"There may be instances where it is not proper to use the injured employee's actual post-injury earnings in determining his or her proportional earnings loss. In establishing their average proportional earnings loss figures, the 2003 and 2004 RAND Studies followed three years of post-injury earnings for 241,685 employees who had sustained industrial injuries over a more than six-year period between January 1, 1991 and April 1, 1997. Given the large number of employees and the broad period of time involved in the RAND Studies, those Studies had no need to consider (and, as a practical matter, probably could not consider) factors that may have skewed the post-injury earnings of particular employees. Yet, when a proportional earnings loss calculation is made for a particular employee in a DFEC rebuttal case, the employee's post-injury earnings portion of that calculation may not accurately reflect his or her true earning capacity. As the Supreme Court stated years ago in Argonaut Ins. Co. v. Industrial Acc. Comm. (Montana) (1962) 57 Cal.2d 589 [27 Cal.Comp.Cases 130, 133] (Montana):

"An estimate of earning capacity is a prediction of what an employee's earnings would have been had he not been injured... [A] prediction [of earning capacity for purposes of permanent disability] is . . . complex because the compensation is for loss of earning power over a long span of time.. . . In making a permanent award [reliance on an injured employee's] earning history alone may be misleading... [A]ll facts relevant and helpful to making the estimate must be considered. The applicant's ability to work, his age and health, his willingness and opportunities to work, his skill and education, the general condition of the labor market, and employment opportunities for persons similarly situated are all relevant.' (Montana. supra. 57 Cal.2d at pp. 594-595 [27 Cal.Comp.Cases at p. 133] (internal citations omitted).)

"Certainly, an individual employee should not be able to manipulate the proportional earnings loss calculation through malingering or otherwise deliberately minimizing his or her post-injury earnings. Similarly, motivational or other factors may play a role in determining whether a particular employee's post-injury earnings accurately reflect his or her true post-injury earning capacity. Further, an employee may voluntarily retire or partially retire for reasons unrelated to the industrial injury. [Citations.] Temporary economic downturns or other factors may also come into play. Accordingly, the trier-of-fact may need to take a variety of factors into consideration.

"The foregoing examples, however, are merely illustrative of some instances where it might be inappropriate to use the method set out above. These examples are neither all-inclusive nor absolute. The question of whether the DFEC rebuttal method discussed above should or should not be used in any particular case must be determined on a case-by-case basis. Moreover, when the foregoing method is not appropriate, it initially will be up to the assigned WCJ to decide what alternative method might be used." (Ogilvie I, 74 Cal.Comp.Cases at pp. 275-276.)"