You do not have to recap your professional history year by year, but detailing the experiences and skills that you have gained as you attained them in an organized fashion will leave a good impression on the employer.
Since humanity's energy needs have been continuously growing year by year, it's possible that eventually we'll need more energy than what we can produce on earth.
In other words, I had worked out from my knowledge of physiology what was the minimum amount of training that would be needed to continue to improve year by year.