You'd have to go back to December 31, 1999, the eve of the millennium, to find a New Year's Rockin' Eve show that attracted more viewers than Saturday's on ABC. The 11 35-12 32 segment of the nearly night-long telecast attracted 22.6 million viewers. Numbers were boosted by the appearance of Lady GaGa, delivering a greatest-hits medley, and Justin Bieber performing the Beatles' "Let It Be," joined during the number by Carlos Santana. The New Year's special has been making double-digit gains for the past three years. Earlier in the evening, a two-hour show featuring clips from 40 years of coverage of the event in Times Square outdrew everything the other broadcast networks put on against them, averaging 8.3 million viewers and peaking in the 9 30 p.m. half hour with 10.5 million. The 10 00 p.m. show, Dick Clark's Primetime New Year's Rockin' Eve with Ryan Seacrest, averaged 12.9 million viewers.