Data from other sources
While the sample of the future study back in 2010 consisted of the four age brackets: 50-54 years, 60-64 years, 70-74 years and 80-84 years, the sample in 2021, just as in 2015, covers all eight five-year age brackets from 50-89 years.
https://www.dst.dk/en/TilSalg/data-til-forskning/generelt-om-data/data-fra-andre-kilder