Comcast Corp\'s NBC and Walt Disney Co\'s ABC broadcast networks are getting closer to wrapping up commitments from advertisers for the television season that starts in September. NBC is averaging 9 per cent rate increases and is two-thirds done with the so-called upfront process through which advertisers reserve space on prime-time shows, a person with knowledge of the sales said. ABC is averaging 10 to 11 per cent price gains and is almost finished, said another person, who wasn\'t authorised to speak publicly. The results are in line with the networks\' ratings performance. NBC, the laggard among the Big Four, is capturing the smallest rate increase. News Corp.\'s Fox, the leader in the 18-49 age group sought by advertisers, drew gains of 10 to 11 per cent, a person said. Largest audience CBS, which attracts the biggest overall audience, is averaging increases of 14 per cent to 15 per cent, a person said June 3. Introducing its first prime-time schedule under Comcast ownership, NBC said last month it would add 12 shows to its schedule, including the police drama Prime Suspect featuring Maria Bello, in a bid to climb out of fourth.