How many albums has your fav. band put out in the 10years since debut.

I had a thought recently, regarding the state of the music industry, and how money apparently is no longer made through albums, but tours etc.
In an adhoc manner and not taking into consideration anything like market trends, band dynamics (i.e. side projects, extensive tours etc) etc, I thought I would look into the amount of releases in the first ten years from debut, from some of legendary bands, and compare it to contemporary high flyers, and Nickleback.

• Black Sabbath: 9 albums (including 1980's Heaven and Hell, 18 total)
• Iron Maiden: 8 albums (including 1990's No Prayer for the Dying, 15 total)
• Judas Priest: 9 albums (including 1984's Defenders of the Faith, 16 total)
• AD/DC: 9 international albums (14 international albums in total) 
• Led Zepplin: 8 albums (including 1979's In through the Our Door, 9 total)

Versus:

• Slipknot: 4 albums (4 total)
• Lamb of God: 5 albums (6 total)
• Machinehead: 5 albums (7 total)
• Tool: 3 albums (4 total)
• Nickleback: 5 albums (7 total)

I am not suggesting that this is indicative of any trend, and I have just randomly picked out band names that I consider to be money earners and have 10years or more existence behind them.

All that I am saying is that, on the surface, it looks interesting that the big legendary names became such by hard word in the making albums department, and that now-a-days there seems to be an overall understanding that money isn't made by selling records, but the number of records put out by bands is a lot less, as much as half in this tiny tiny sample.