Most of the Korean sales on this blog come from GAON which is linked to KMCIA, The Korean Music Content Industry Association. Before the KMCIA there was MIAK, the Music Industry Association of Korea which ran from 2002 to 2008. It would provide both digital and album sales information for the industry and had archives going back to 2001 1999, which unfortunately no longer exists except for a few screencaps. I am translating what I can find.
Sometimes total means for the year but more often total means since release regardless or year.