You could also just cap it 49 or 54 years old. A lot of medical research does this when looking into things like cancers. It gives a pretty good indication of whats going on during early and prime year without as much longevity bias or 'old age/natural causes' deaths skewing the data. If you make it fully age weighted then you might adjust away things like murder for the 35+ crowd, or overinflate things like SIDS, drowning, and childhood cancers.