data quality - age
On the 2019-06-19 data there are 233 records with an Age, but no AgeClass.Eyeballing them, we seem to have a bunch of infants competing!
First entry is Svetlana Kovaleva, who reappears 15 years later, so I think we've got a bunch of entries where the script has tried to match records based on Name, but hasn't had a sanity check that 3.5-year-olds probably aren't the same person. (Some others ended up logged at 0.5 years old.)