Rule 43 of CGST Rules, 2017

In Rule 43 of CGST Rules, 2017 :
*CASE* : When a capital good which was previously used for effecting exempt supplies only and thereafter used for effecting both exempt as well as taxable supplies, then amount of input tax credit shall be arrived at by reducing 5% of input tax for every quarter or part thereof.
In the above case, the quarter mentioned above will be taken as a calendar year quarter or to be calculated from the date of procurement of capital good?