Because age discrimination is prevalent in hiring in the US & Canada, we recommend leaving off any jobs that ended before 2005. Or more precisely, summarizing them all by title and company name in the “prior experiences” section of your resume.
Your experience in the past 5 years is the most relevant information for a hiring manager. It’s what you’ll most likely be asked about in an interview, screened on, and will be the basis for any hiring decision. The past five years have the greatest impact on what jobs you will be invited to interview for, what jobs you’ll ne offered, and what job you ultimately accept.
The decade prior to those five years is relevant, but less so. The ten years leading up to this most recent time period is the time during which you developed your capabilities, matured as a professional and manager, and cut your teeth in dozens of different situations. Hiring managers like to see this background as it helps them understand the past half-decade even better.
Experience beyond 16 years ago is simply not relevant to the hiring manager today. It’s ancient history that has little to do with your ability to perform in a job today. The work that you did and the tools that you used are not applicable to the challenges of today. And your performance in those long-ago jobs isn’t linked to your likely performance in your next job with your future employer.
We never hear recruiters or employers say, “The reason the person is getting the interview is because of their terrific experience in 2002 with…” or “What this candidate achieved in 1997 is awesome, and exactly the type of person we need at our company today.”
As a rule, if something is not actively helping you get interview requests, it doesn't belong on your resume. And in the case of specific dates from two or more decades ago, there is the potential harm of age discrimination.
Therefore, we’ll generally leave the details and years regarding your work experiences that ended before 2005 off of your resume.