I am not even sure if this can be answered on this forum but I figured that Google Drive Sheets logic should not be far off original Excel. Sorry if this is out of place.

I am using Google Drive to generate a chart.
I have a file where I log some events from my IoT equipments.
By using IMPORTRANGE function, I import this data into another file and use it to build a chart.
I am looking for a way to use only last 100 data points for a chart but could not find how to do that. Chart building menu offers to select a range but this is not dynamic selection. IMPORTRANGE is also limited to all or nothing (if I got it right).
I need to keep logging the data in the first file but only import last 100 points into my new file

Please help