CSN_data_2011_VIEWS.gz.csv (1.6 MB) Hi Trang,
Perhaps the issue is that the CSN file itself is not sorted. Please try using the attached CSN_data_2011_VIEWS.csv file and see if that solves the issue. Note that the file I’ve attached is actually a gzip file. So, after you download it you’ll need to rename from .gz.csv to .csv.gz and then unzip it.
Once you do that try using the new file and let me know the result. Thanks.
Wyat