diff --git a/src/linkgraph/flowmapper.cpp b/src/linkgraph/flowmapper.cpp
index 79e03b0123..b7a43f2562 100644
--- a/src/linkgraph/flowmapper.cpp
+++ b/src/linkgraph/flowmapper.cpp
@@ -53,7 +53,7 @@ void FlowMapper::Run(LinkGraphJob &job) const
 			/* Scale by time the graph has been running without being compressed. Add 1 to avoid
 			 * division by 0 if spawn date == last compression date. This matches
 			 * LinkGraph::Monthly(). */
-			uint runtime = _scaled_date_ticks - job.LastCompression() + 1;
+			uint runtime = ClampTo<uint>(DateTicksToScaledDateTicks(job.StartDateTicks()) - job.LastCompression() + 1);
 			for (auto &it : flows) {
 				it.ScaleToMonthly(runtime);
 			}
diff --git a/src/linkgraph/linkgraphjob.h b/src/linkgraph/linkgraphjob.h
index 9770bdd6c7..ddd1113653 100644
--- a/src/linkgraph/linkgraphjob.h
+++ b/src/linkgraph/linkgraphjob.h
@@ -346,7 +346,7 @@ public:
 	 * Get the date when the underlying link graph was last compressed.
 	 * @return Compression date.
 	 */
-	inline Date LastCompression() const { return this->link_graph.LastCompression(); }
+	inline DateTicksScaled LastCompression() const { return this->link_graph.LastCompression(); }
 
 	/**
 	 * Get the ID of the underlying link graph.