*Plays are calculated by the quantity of times all the people listened to any song off the albums during the tracked week, the number of total Plays will give certifications (250k Silver, 500k Gold, 1 million Platinum, 10 millions Diamond)
*Catalog Songs shows the most popular old songs of the week, the songs had to be released as singles before this day: January 1st, 2011. If a song that wasn't released as a single could chart, the album (or wherever it belongs) had to be released before that date as well.
I count EACH countdown that has been updated on the tracked week, so I see each songs that a person likes, and in what positions they have it. I count each song, so if the chart is a "Top 40", "Top 30", "Top 15" or whatever, I count each song, but obviously a lot of them don't even make it to the 300th position XD.
So depending in the position each person has a song I give them points, then over last.fm I see how many people listened to a song on the week and I use that number as a population sample, so if 76 people of 260 on the group listened to a song it's obvious that at least 1,026+ ATRLers listened to the song, so I gave them points depending of how many ATRLer listened to it.
Then I take the Billboard different charts' positions and gave the chart those points, right now it's only about a 10% of the complete tally, so it's more considered as a "Bonus Points".
Popularity is really different, I check ATRL at least once a day, and I always check what new threads are made, and what artist is being mentioned the most, so I gave them those popularity points, so I tracked each chart from each Tuesday to Monday, in example, let's say Madonna is being mentioned a lot with her song "Give Me All Your Luvin'", so that song will have some popularity points, though Popularity points are about 1% of the total tally which is... really nothing.. though they can make a change if a song has 24% and other has 24.01% points, so the song with 24% can reach to 24.02% and take a taller position that the one with 24.01% that wasn't popular this week.
Because the chart has more than 13,000 followers on twitter and they became attached to the tally, they now give their own list of songs they like, so this counts as another bonus for each chart (there are a lot of Latin followers, which increased the activity on Latin charts); it isn't a problem to add them because they lurk ATRL but haven't joined, so they are ATRLers, even if they haven't officially joined.
2.- Where do you count the listens for the albums?
Everything is statistics, I just see how many people listen to the album, then check to how many songs of the album they listened to (in the singles, mostly, the Airplay Songschart), then make an equation and see the total estimated numbers of plays each albums has.
This works as a sample of the total population (I studied marketing where we learn how to make this, it's just like how Billboard does with their Airplay Charts, do you think they actually track all 150 millions of AI?, no )
Plays: The number of times A SONG of the album was played. So just it woulb be
# of plays of track #01 +
# of plays of track #02 +
# of plays of track #03 +