(c) Evidence of a test's validity should consist of empirical data demonstrating that the test is predictive of or significantly correlated with important elements of work behavior which comprise or are relevant to the job or jobs for which candidates are being evaluated.

1. (1) If job progression structures and seniority provisions are so established that new employees will probably, within a reasonable time and in a great majority of cases, progress to a higher level, it may be considered that candidates are being evaluated for jobs at that higher level. However, where job progression is not so nearly automatic, or the time span is such that higher level jobs or employees' potential may be expected to change in significant ways, it shall be considered that candidates are being evaluated for a job at or near the entry level. This point is made to underscore the principle that attainment of or performance at a higher level job is a relevant criterion in validating employment tests only where there is a high probability that persons employed will, in fact, attain that highest level job within a reasonable period of time.
2. (2) Where a test is to be used in different units of a multiunit organization and no significant differences exist between units, jobs, and applicant populations, evidence obtained in one unit may suffice for the others. Similarly. where the validation process requires the collection of data throughout a multiunit organization, evidence of validity specific to each unit may not be required. There may also be instances where evidence of validity is appropriately obtained from more than one company in the same industry. Both in this instance and in the use of data collected throughout a multiunit organization, evidence of validity specific to each unit may not be required: Provided, that no significant differences exist between units, jobs, and applicant populations.