That seems odd and I am actually shocked by that. I think I grew about 2 inches between 16 and 19. Was shortish in highschool. Comfortable height now.
But fair enough. Maybe he wont grow
The 2mm stat is quite conservative compared to the best sources we have from the CDC. Keep in mind, this is
American kids. There's one issue, these charts are rarely specific to Russian athletes living in Canada. Worldwide charts would have to account for nutrition and accuracy of data, in addition to ethnicity.
In the US, the 50th percentile increases about 1.5 inches between ages 16 and 20. What that means is the
average height for boys goes up 1.5 inches between those ages. This doesn't tell us exactly how much you can expect any one person to grow, but it does tell us that boys still are expected to see some growth after 16. The numbers we see on these charts show movement quite a bit more than 2mm.
Here's said chart used by health folks:
http://www.cdc.gov/growthcharts/data/set2/chart-07.pdf