diff --git a/monitors/apt.py b/monitors/apt.py
index ad5cb54..3d3e969 100644
--- a/monitors/apt.py
+++ b/monitors/apt.py
@@ -10,4 +10,4 @@ class APT:
     def run(self):
         stream = os.popen('apt list --upgradable 2>/dev/null | wc -l')
         output = stream.read()
-        self.exporter.gauge("apt.upgradable", int(output))
+        self.exporter.gauge("apt.upgradable", int(output) - 1)