I served in the Air Force from 1966 to 1970 and started working for the Defense Department in 1970. My CSRS retirement contributions started at that time, and my service computation date was listed as Dec. 12, 1966. When I retired on Oct. 1, 2011, I had worked for the DoD for 40 years and nine months (44 years and nine months with my Air Force time included). With my four years of Air Force time included, I reached my 41 years and 11 months in November 2008, since I continued to work until October 2011. I thought that my retirement contributions from December 2008 (41 years, 11 months) to Oct. 1, 2011, would be returned to me. I am now being told that that is not the case.