diff --git a/echo-client.rkt b/echo-client.rkt
index 319a44e..dbc06ca 100644
--- a/echo-client.rkt
+++ b/echo-client.rkt
@@ -113,7 +113,9 @@
 	(loop (+ count 1))
         (when record-results?
           (let* ((elapsed-sec (/ (- now start-time) 1000.0))
-                 (roundtrip-latency (/ elapsed-sec count)))
+                 (roundtrip-latency (if (zero? count)
+                                        elapsed-sec
+                                        (/ elapsed-sec count))))
 	    (write-logbook-datum! Tping (list (connection-count)
 					      roundtrip-latency
 					      (/ 1.0 roundtrip-latency)