I haven’t checked out their app, but performed a similar exercise on their website (under the Prices menu, select bitcoin). The information displayed is not exactly the same, but if we compare we’ll see that:
- The 1 day view Y axis ranges from 47K to 51K
- The 7 day view Y axis ranges from 47,5K to 57,5K
Those scales do not represent the max/min values though on the website, as the app seems to suggest it does. Nevertheless, if I chose a datapoint in the 7 day window, it coincides in value with the 1 day window reading (as expected), but, the granularity of the x axis data points is different on both views:
The x axis datapoints are 5 minute readings on the daily scales, whilst being 30 minute apart on the 7 day view. That means that the weekly view captures 1 in 6 of the data points shown in the daily view, losing out the representation of 5 out of 6 values. The coincidential reading has the same value (it does not average it out for the 6 data points).
I can only think that the charts on the app follow a similar logic, and that the daily chart, being more granular, catches more data points (and therefore dips in this case) than the weekly chart. That would mean that the max/min shown are relative to the datapoints, but are not absolute max/min readings necessarily.
Pretty stupid, don't you think? If data is already being read every 5 mins, that reading could just be logged and applied to be displayed at whatever time intervals you choose. What am I missing?