Generator Decrement Curve

Hi all, I'm trying to calculate how SKM Powertools (power system modelling software) comes up with this initial value for the generator decrement curve:

Paramaters im using: Xd"=.15pu, Xd'=.21pu, Xd=.5523pu; Td"=.025s, Td'=.42s, Ta=.04s, Sbase = 800kVA, Vbase=415V, generator is running at 1.06*415V supply

My calculations are as follows:

Xd(base) = Vbase^2/Sbase = 415^2/800k = .21ohms

Xd"(ohms) = .15 * .21 = .0315 I(symmetrical) at t~=0s: (1.06*415)/(1.73*.0315) = 8.148kA

Why does SKM list the current value at .01s as 6.7kA (symmetrical)? I think that is too low...