As far as I know, there are no centenarians in my ancestry. However, a combined group of family members descended from my immigrant great-grandparents worked in the post office system in Duval County, Florida, just short of 100 years.
My great uncle, Louis Damato, started working at the post office in 1911. He started as a clerk and became a foreman in 1927, an assistant superintendent of West Bay Station in 1943, the foreman of mails in 1955, and tour superintendent of West Bay Annex in 1960 until he retired in 1963. Uncle Louis actually held (and may still hold) the longevity record for continuous service at the Duval County post office system – 52 years. 
While Louis worked, other relatives followed his lead. His son Richard worked in the art department of the post office as an artist-illustrator who created posters. His nephews, John Anthony Damato, Jr. and Joseph Damato, Sr., found work at the post office after World War II and military careers. His niece, Angelina Bell Damato, met her husband, Al Duncan, while working at the post office.
The Damato tradition of landing jobs at the post office continued to the third generation of descendants of Italian immigrants Joseph and Angelina Previti Damato. Louis’ great nephews Tony Damato and Joseph (Joey) Earl Damato were the last of the Damato descendants to work for the postal service. Joey was a walking mail carrier at Neptune Beach. His sudden and untimely death on New Year’s Eve 2010 ended the tradition for the family just short of 100 years by a few months. 
Angelina Bell Damato Duncan stated in a 1981 letter to her extended family, “Our motto once was ‘the sun never rises or sets that there is not a Damato in the post office.’”
 “Post Office Supervisor Louis Damato Retires at 70 After 52 Years Service,” The Florida Times-Union, 4 November 1963.
Larry Hannan, “Death of Neptune Beach Man Ends 100 Years of Family Service at Post Office,” The Florida Times-Union, 8 January 2011, (http://www.jacksonville.com/news/metro/2011-01-08/story/death-neptune-beach-man-ends-100-years-family-service-post-office : accessed 22 February 2018).