She said top-tier bonuses were partly dependent on gender diversity.
Ms Chapman said CBA made it mandatory to have both a man and woman on the panel when employing for senior roles.
"It encouraged women inside the business to put themselves forward," she said. "Also it made the men and the women involved in the interview process look differently at the female candidates and have more serious discussions about who was right and wrong for the job."
According to a gender equality report published last year by the Economic World Forum, New Zealand is the sixth-best country for women to live in, a step back from the position of fifth held in 2010.
Ms Chapman said New Zealand has all the correct anti-discrimination laws in place to ensure equality but says not enough is being done in the work and corporate sector.
"I think all the legislative pieces are in place, there is no doubt that we've got good anti-discrimination law ... I think what we don't have is a real track record of progress."