Hi Kari,
Thank you very much for your reply. I’m pretty sure the 999,999’s recorded in the 1860-1880 and 1870-1880 samples should indeed be recoded as zero, but it would be nice to have a confirmation of that (and perhaps a link to some documentation?), since I didn’t see any documentation online. This is for a scholarly article and I just want to fully satisfy the reviewers on this point.
Thanks again for looking into this and take care,