When doing a Roth conversion of a non-deductible contributions from traditional IRA . is a rollover IRA included in the list of all IRA balances to determine tax free %

I have currently two  IRA accounts . 1. Rollover IRA (401k from previous employer),  2. Roth IRA.  with some balance in each.
I want to do a backdoor IRA by opening a new Traditional IRA account , add $ and then move that amount to the Roth IRA .  I was told that  the below computation needs to be applied to calculate what percentage of the transfer is tax free
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  Tax-Free Percentage=  TND / (YV C)  
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where:
TND=Total non-deductible contributions
YV=Sum of year end value of all IRA accounts
C=Conversion amount
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my Question is ,  should the balance in Rollover IRA be included in calculating YV from above .