How to read these charts: On the y-axis (vertical axis on the left), you'll see 0. That is the 'baseline'. What does that mean? It's the 'normal' amount of movement on that day of the week before the pandemic. Movement on Sundays is different from Wednesdays, so each day has its own normalised baseline. Google has calculated 'normal' for each day of the week, by finding each day's median during a five week period from 3 January to 6 February 2020. That means the baseline is summer holidays / wet season in Australia. Keep that in mind when comparing current data with the baseline. For more, read this Twitter thread. Data updated daily; most recent date will be ~5 days ago.