diff --git a/tasks.c b/tasks.c
index d63f6ccfd..c057973d1 100644
--- a/tasks.c
+++ b/tasks.c
@@ -393,7 +393,7 @@ PRIVILEGED_DATA static volatile UBaseType_t uxSchedulerSuspended	= ( UBaseType_t
 	/* Do not move these variables to function scope as doing so prevents the
 	code working with debuggers that need to remove the static qualifier. */
 	PRIVILEGED_DATA static uint32_t ulTaskSwitchedInTime = 0UL;	/*< Holds the value of a timer/counter the last time a task was switched in. */
-	PRIVILEGED_DATA static uint32_t ulTotalRunTime = 0UL;		/*< Holds the total amount of execution time as defined by the run time counter clock. */
+	PRIVILEGED_DATA static volatile uint32_t ulTotalRunTime = 0UL;		/*< Holds the total amount of execution time as defined by the run time counter clock. */
 
 #endif