diff --git a/docs/syntax.md b/docs/syntax.md
index 39e56ab..de67284 100644
--- a/docs/syntax.md
+++ b/docs/syntax.md
@@ -408,6 +408,7 @@ Parts can be added to a connector or cable in the section `<additional-component
                   # when used in a connector:
                   # pincount         number of pins of connector
                   # populated        number of populated positions in a connector
+                  # unpopulated      number of unpopulated positions
                   # when used in a cable:
                   # wirecount        number of wires of cable/bundle
                   # terminations     number of terminations on a cable/bundle
diff --git a/src/wireviz/wv_bom.py b/src/wireviz/wv_bom.py
index 01fbac3..cf5c04f 100644
--- a/src/wireviz/wv_bom.py
+++ b/src/wireviz/wv_bom.py
@@ -31,7 +31,7 @@ BomCategory = IntEnum(  # to enforce ordering in BOM
     "BomEntry", "CONNECTOR CABLE WIRE ADDITIONAL_INSIDE ADDITIONAL_OUTSIDE"
 )
 QtyMultiplierConnector = Enum(
-    "QtyMultiplierConnector", "PINCOUNT POPULATED CONNECTIONS"
+    "QtyMultiplierConnector", "PINCOUNT POPULATED UNPOPULATED CONNECTIONS"
 )
 QtyMultiplierCable = Enum(
     "QtyMultiplierCable", "WIRECOUNT TERMINATION LENGTH TOTAL_LENGTH"
diff --git a/src/wireviz/wv_dataclasses.py b/src/wireviz/wv_dataclasses.py
index ded141a..8563b87 100644
--- a/src/wireviz/wv_dataclasses.py
+++ b/src/wireviz/wv_dataclasses.py
@@ -450,6 +450,7 @@ class Connector(TopLevelGraphicalComponent):
         qty_multipliers_computed = {
             "PINCOUNT": self.pincount,
             "POPULATED": num_populated_pins,
+            "UNPOPULATED": self.pincount - num_populated_pins,
             "CONNECTIONS": num_connections,
         }
         for subitem in self.additional_components: