in applying the “unprotected class membership” standard rather than the “sufficiently younger” standard as the fourth element of the McDonnell Douglas prima facie test. In order for a plaintiff to satisfy the “sufficiently younger” standard, we have noted that there is no “particular age difference that must be shown,” but while “[different courts have held ... that a five year difference can be sufficient, ... a one year difference cannot.” Sempier v. Johnson & Higgins, 45 F.3d 724, 729 (3d Cir.1995) (citations omitted). In this case, Showalter was eight years older than Leahy and 16 years older than Wright. We hold that the differences in age between Showalter and the retained employees were sufficient to satisfy the fourth element of a prima facie case. See Sempier, 45 F.3d at 730 (<HOLDING>). B. We now turn to Showalter’s second
holding that the fourth prong of a prima facie age discrimination case was satisfied where plaintiff was replaced by two individuals  one who was four years younger than plaintiff and the other who was ten years younger holding when an employee was temporarily replaced by a person who was 10 years younger and permanently replaced by a person four years younger this was sufficient for the prima facie case holding that being replaced by someone outside the protected class is not a proper element of the fourth prong because replacement by a substantially younger employee is a far more reliable indicator of age discrimination holding that adea plaintiff had failed to make a prima facie case of age discrimination when he was replaced by someone only two years younger and within the protected age group and there was no other evidence of age discriminatory motive holding in a rif context that the fourth prima facie element is satisfied if the plaintiff can show that he was discharged while the company retained someone younger