Managed to work out the figures, with someone mentioning that 10 is the max you can allocate…
# of SCVs for Command Center build time
1 100
2 62.5
3 45.45454545
4 35.71428571
5 29.41176471
6 25
7 21.73913043
8 19.23076923
9 17.24137931
10 15.625 <<< MAX
11 14.28571429
12 13.15789474
13 12.19512195
14 11.36363636
15 10.63829787
16 10
17 9.433962264