Sapi - Thanks for fixing the title.

Foz- What you say makes sense.

To confirm the theory I ran the test again with Bill Militia, that also has a total missile resistance of 0. The result were

Attacking Unit type-----------Lost----------Kills
Bill Militia--------------------391----------156

This fits the theory.

This made me wonder what results melee defenders would give. So I retested this time giving Magdeburg to the Papal States who garrisoned it with -

4 units of Mailed Knight.
2 units of Mounted Sergeants
2 units of Dismounted Feudal Knights.
All Melee - No Ranged units

The results were -

Attacking Unit Type-----------------Lost----------Kills

Armoured Swordsmen--------------59--------- 202
Feudal Knights--------------------88----------213
Retinue Longbowmen-------------129----------208

Town Militia----------------------288----------100------defeat
Hobilar---------------------------317----------84------defeat
Militia Archers--------------------354----------50------defeat

This is the same order as for the ranged defenders. Maybe because the settlement has so many towers, that inflict missile damage, the calculation assumes that all the defenders inflict missile damage?