2014: February, April, June
2013: February, May, June, September, December
2012: February, March, June, September, November
2011: February, April, July, October
2010: October
2009: February, April, May, July, October
2008: January, February, March, April, July, August, October
2007: January, March, May, June, July, August, October, November
2006: January, February, March, June, July, September, October, November, December
2005: January, February, March, April, May, June, August, September, October, November, December
2004: January, March, April, June, September, October, December
2003: September, October, December