Work from home expenses - in a hybrid role

[Susiecube1]

TurboTax requires annual expenses of heat, hydro, electricity and water for T777, work from home expenses. Previous versions of TurboTax required a user to input the actual number of days worked from home. This field no longer exists. 

If two different users had the identical expenses and Employee A worked 111 days from home whereas Employee B worked 256 days from home, the allowable expenses calculated should be very different.

So how do we calculate this, especially in the very common hybrid work role?