Data refreshing time too long

I have daily file in folder to summaize, about 1 months of records have been stored.

But everytime a new file stored in the folder, I need to refreshing the report so to get the cumulative summaize, and it take long time to refresh the data as PBI will refresh all the data start from beginning.

Is there any way to keep the historical data already imported to the report and only refresh the latest file?