If any one sees these posts, I have added in a JSON call for the CPI which you can bring into a google sheet. I will see if I can write some script which gives users a working example.
Happy to provide importjson script for a google sheet and to show anyone who is interest how to set up a call direct from the ABS into a google spreadsheet. Here is a link to the script for the google sheet.
ImportJSON/ImportJSON.gs at master · bradjasper/ImportJSON · GitHub and below is a formula to make an API call for the CPI data -