Etabs 13 base shear calculation check according to UBC97

[BOCH]

Hi guys,
I would like to share with you this incidence,
I was running an Etabs 13 model and checking the calculated base shear (according to UBC97),
This is what I have got (image attached),

The used period to calculate the base shear in X direction was not taken as per the “Modal direction factor table” which indicate that the period in X direction is 0.469s with a 76.3% participating ratio ..
Am I missing something here ?

 

[structural87]

Can u post ur model so we can have a look ?