I was doing research to compare the price of an alpha card against the growth of the magic community. In order to do this, I had to do some research on the size of the community. I found random articles all over the place, which of course I did not site. This is what I've found:

1997-8: 5 million players

1999: 6 million players

2000: 7 million players

2001: 5 million players

2002-2006: 6 million players

2007: 7 million players

2008: 6 million players (Magic was at this point considered a declining property)

2009-0: Unstated but probably in the 7-8 million range. They had 25% growth annually during this time

2011: 10 million players (Innistrad brought it back with a vengeance)

2012: 12 million players (from here they claim 35% growth year over year, and i don't doubt it)

2013: 16.2 million Players (35% growth from 2012)

2014: 21.87 million Players (35% growth from 2013)

Additional Sited research

  • 2013 — "Magic" now has 12 million active players globally, and Hasbro said that it's the biggest brand in its $1.2 billion games portfolio. In its 2012 annual report, the company said that "Magic's" revenue has grown by 25 percent or more in each of the previous four years. — NBC 2013 https://archive.is/EQaiY
  • 2016 — In Hasboro's earning report, they state there are 1 million registered DCI players, and 65,000 playing in the grand prix. You must figure there are 10 to 20 casual players for every serious DCI player, putting the estimates in the 15-21 million range. http://files.shareholder.com/downloads/HAS/1985039992x0x886266/F7E883EE-DCA4-4FBA-B556-947855949722/HAS_News_2016_4_18_Quarterly_Financials.pdf