That's funny, because when I go to the Pew site it says this:
The Veterans Survey (V)
The attitudes of veterans reported in this study are based on a nationally representative sample of 1,853 men and women who served in the military and are no longer on active duty. The sample included 1,134 who were discharged from the military prior to Sept. 11, 2001, and 712 veterans who served after 9/11. (Seven veterans declined to answer when they served.)
The margin of sampling error for results based on the entire sample of veterans is plus or minus 3.5 percentage points; the margin of sampling error for the pre-9/11 sample is plus or minus 3.9 percentage points; and the margin of sampling error for those who served after 9/11 is plus or minus 5.7 percentage points.
Veterans were interviewed by telephone or via the internet. A total of 1,639 interviews were conducted over the telephone under the direction of Social Science Research Solutions (SSRS). Respondents had been identified as veterans in earlier surveys conducted by SSRS and the Pew Research Center and were re-contacted for the veterans survey. Of the total sample, 1,307 telephone interviews were conducted on landline telephones and 332 on cell phones. Interviewing for the telephone survey was conducted from July 28 to Sept. 4, 2011. These interviews were supplemented by 214 interviews with veterans who served after 9/11 and are part of random sample panel of households maintained by the research firm Knowledge Networks. These online interviews were collected Aug. 18-31, 2011.
The two data sets were combined and the entire sample weighted by SSRS to match known demographic characteristics of the veterans population as reported by the U.S. Census Bureau. In addition, the post-9/11 oversample was weighted back to reflect its correct proportion of the overall veterans population. A detailed explanation of the survey methodologies and weighting strategy employed in this study is in Appendix 1.
For the full report:
War and Sacrifice in the Post-9/11 Era | Pew Social & Demographic Trends