Brian Steinberg Senior TV Editor The bill may be coming due for continued declines in TV ratings. Advertisers are pressing for rollbacks, or declines in the rates they pay for reaching TV viewers, in early “upfront” talks with TV networks, according to two media buying executives and other people familiar with these annual discussions in which U.S. media companies try to sell the bulk of their commercial inventory ahead of their next cycle of programming. Agreements that include reductions in these rates, also known as CPMs and a measure of the cost of reaching 1,000 viewers, have generally been extremely rare, and offer a signal that the continued migration of viewers to streaming and digital-video options is eroding the marketplace leverage of both traditional TV companies and some of their new-tech rivals as well.