Workflow - problem with counting the value of the field depending on filling in another

Hello,

I have a problem with calculating the percentage for my fields.
Example:
field_1 = 20 and field_1.1 = 10
field_2 = 20 and field_2.2 = 10
field_3 = 20 and field_3.3 = 10
field_4 = 20 and field_4.4 = 10
field_5 = 20 and field_5.5 = 10
field_6 = 20 and field_6.6 = 10

sum field_1,2,3,4,5 = 120
the sum of the field _1.1,2.2,3.3,4.4,5.5 = 60

sum_% = ((sum field_1,2,3,4,5,6) / (total field _1.1,2.2,33,3,44,5,5.6.6)) * 100
sum_% = 200%


It is simple. But what is the calculation of sum_% when one or a few fields are not filled and then I have to calculate the percentage? My problem is like this:

When one of the fields has the value "0", the second one should be taken into account but only if the next field has the value > "0" np.