Index: uspace/app/tester/ipc/ping_pong.c
===================================================================
--- uspace/app/tester/ipc/ping_pong.c	(revision e131bd05cd3ced3b445c51035c8943d3ead77524)
+++ uspace/app/tester/ipc/ping_pong.c	(revision 790f3a3a7e4d0de0dc62be56505cd98a8966eaef)
@@ -127,5 +127,5 @@
 	}
 
-	double stddev = qd; // XXX sqrt
+	double stddev = qd / (NUM_SAMPLES - 1); // XXX sqrt
 
 	TPRINTF("Average: %.0f rt/s Std.dev^2: %.0f rt/s Samples: %d\n",