From the time the first merged list came out in October of '08, until yesterday, we have had 613 pilots retire, resign, get canned, or otherwise "depart" the seniority list. Pretty sure the vast majority of those pilots were under 65. Here's how it breaks down by year:

Oct - Dec 2008: 10
2009: 203
2010: 156
2011: (YTD) 244

Also of note: We added 235 new bodies in 2010, so net loss of pilot positions since the merger is 378, thus far.