‘When we grow, I hope all of television grows’: Growth key as official TV ratings year begins Ahead of the beginning of the official ratings period today, Mumbrella's Brittney Rigby spoke to Seven's Kurt Burnette, Ten's Rod Prosser and Nine's Hamish Turner about 2021 slates, the Australian Open and Olympics, BVOD strategies, and which competitor shows they're keeping the closest eye on. February 8, 2021 9:38 Today marks the beginning of the official TV ratings year. While OzTam records ratings across the entire year and “declares no official ratings period”, the networks’ official count runs for 40 weeks, pausing for two weeks over Easter, and 10 weeks over summer.