Hmmm, in VIC I pay $0.96/day supply and usage rates of about 16c/kWh. Maybe prices vary a lot by location, because the prices I pay bear no resemblance to those on the chart...
Possibly relevant: I do look at my usage and compare providers and I am with what appears to be the cheapest possible provider for me (according to https://compare.switchon.vic.gov.au, with smart meter data providing a very accurate basis for the comparison).
And having mentioned that, I thought that it had been a while since I checked... Seems I can get $0.72/day supply and 14.9c/kWh now, I guess it's time to change.