As a follow-up to my post about the demise of the middle tail, here are graphs that show sales over the last three years for albums ranking at #150, #100, #80, #40 and #10. They are in separate graphs; putting them all in one graph got a bit messy.

As I did for the previous post, I plotted weekly sales figures at roughly four-week intervals over the last three years. The downward sloping trend lines tell the story. At each different point on the album chart, per-week sales have dropped steadily over the last three years. The telling part is the difference in the rate of decline depending on the ranking on the album chart.

Looking at sales in the summer of 2007 versus the summer of 2004, here are the compound annual growth rate of each ranking. I calculated this based on the average over four-week periods in June/July of 2004 and 2007. An average is better than comparing any two comparable weeks because of natural volatility in sales numbers.

• #200: -11.8%
• #150: -14.0%
• #100: -16.4%
• #80: -15.9%
• #40: -11.5%
• #10: -6.7%
• All albums: -7.6%

The numbers show that the #10 album fares well compared to overall album sales, but for all other rankings the rate of decline over the last three years has been greater than the rate of decline for all album sales. The decline is greatest in the middle of the Top 200. At #80 and #100, the rate of decline is the largest in the sample.