Here are a selection of charts GAON has published:
This chart shows the DAs of the #1 song of the week on GAON starting from 2NE1's Falling in Love, which was the last song with over 30 million DAs until Busker Busker released Love, At First, to last week's #1, IU's The Red Shoes. It shows the general DA slump the industry has been in the last couple of months.
This chart shows the total DAs of the Top 10 in the given weeks. The 5th week is the week Busker Busker released their album while the last week is the week IU released her album. The DAs of the songs in the Top 10 this past week, which is the last one on the graph had a total of 163,080,660 DAs.
This one shows the ratio of streaming to downloads in percentage for the songs that were #1 in downloads in recent weeks. This shows how a song with a high ratio of streaming, rather than downloads, will have lower DAs. (light green is streaming and dark green is downloads).
Songs are (from left to right): Busker Busker's Love, At First, IU's The Red Shoes, Mad Clown and Soyu's Stupid in Love, Yoon MiRae's Touch Love, Exo's Growl, and Bumkey's Attraction.
While streaming accounts for up to 40% of daily and realtime charts on music sites, it is not as reflective on sales as streaming does not bring in as much revenue as downloads.
For more information see the source: http://gaonchart.co.kr/thema/view.php?id=89&gbn=opinion