SBS is working with TV ratings agencies, including OzTAM, to increase the representation of homes with English as a second language in surveys, saying the size of its audience is being understated because ethnic households are not properly measured. In a separate but related concern, the network also believes the audience for its new national indigenous TV channel NITV is being significantly underreported because the regional survey sample does not include homes in the Northern Territory, Darwin, regional South Australia or the top end of Western Australia, where many Aboriginal viewers live.