diff --git a/lib/icinga/perfdatavalue.cpp b/lib/icinga/perfdatavalue.cpp
index 4f090d494..2d1fc1864 100644
--- a/lib/icinga/perfdatavalue.cpp
+++ b/lib/icinga/perfdatavalue.cpp
@@ -124,7 +124,7 @@ String PerfdataValue::Format(const Value& perfdata)
 		PerfdataValue::Ptr pdv = perfdata;
 		std::ostringstream result;
 
-		result << pdv->GetValue();
+		result << Convert::ToString(pdv->GetValue());
 
 		String unit;