Seems broken? Tells me I have 60-some percent of my life remaining (I was born 1964, when I return to settings it seems stuck on 1992 - for which 60% would make sense).
A calculator which is much easier for me to use and gives more reasonable results is https://www.ssa.gov/OACT/population/longevity.html Its inputs are gender and date of birth. Gender has a big effect on life expectancy. This one shows 2.7 years left and a total estimated lifespan of 98.7 years. By this calculation he has about 3% of his life remaining.
Easy bug to fix? LASt the very least I expect it to pick some arbitrary day of the month I enter.
I should tell my dad though that he is has about 13 weeks left to live. (Or should?)
The website is seriously malfunctioning. I guess it's just giving results of a different user.