Hi Srikar,
Analysis for office goes directly to SAP BW / SAP HANA for data retrieval, so there is no need to consider it as part of your sizing exercise.
There is a note though about client Hardware and Software requirements:
1466118 - Hardware & Software requirements for Advanced Analysis
The only exception here is the new scheduling capability of Analysis for Office in the BI Platform, in that case the Adaptive Job Server is used.
Best regards,
Victor