diff --git a/libtransmission/stats.c b/libtransmission/stats.c
index a8916b287..1ab4ff521 100644
--- a/libtransmission/stats.c
+++ b/libtransmission/stats.c
@@ -140,7 +140,7 @@ tr_getSessionStats( const tr_handle   * handle,
 {
     const struct tr_stats_handle * stats = handle->sessionStats;
     *setme = stats->single;
-    setme->ratio = (double)setme->uploadedMiB / (double)setme->downloadedMiB;
+    setme->ratio = setme->downloadedMiB ? (double)setme->uploadedMiB / (double)setme->downloadedMiB : TR_RATIO_NA;
     setme->secondsActive += (time(NULL) - stats->startTime );
 }
 
@@ -150,7 +150,7 @@ tr_getCumulativeSessionStats( const tr_handle   * handle,
 {
     const struct tr_stats_handle * stats = handle->sessionStats;
     *setme = stats->cumulative;
-    setme->ratio = (double)setme->uploadedMiB / (double)setme->downloadedMiB;
+    setme->ratio = setme->downloadedMiB ? (double)setme->uploadedMiB / (double)setme->downloadedMiB : TR_RATIO_NA;
     setme->secondsActive += (time(NULL) - stats->startTime );
 }
 
diff --git a/macosx/StatsWindowController.m b/macosx/StatsWindowController.m
index 6ccee04ad..053eb14a0 100644
--- a/macosx/StatsWindowController.m
+++ b/macosx/StatsWindowController.m
@@ -88,8 +88,11 @@ tr_handle * fLib;
                                             stringByAppendingString: NSLocalizedString(@" total", "stats total")]];
     
     [fRatioField setStringValue: [NSString stringForRatio: statsSession.ratio]];
-    [fRatioAllField setStringValue: [[NSString stringForRatio: statsAll.ratio]
-                                    stringByAppendingString: NSLocalizedString(@" total", "stats total")]];
+    
+    NSString * totalRatioString = statsAll.ratio != TR_RATIO_NA
+        ? [[NSString stringForRatio: statsAll.ratio] stringByAppendingString: NSLocalizedString(@" total", "stats total")]
+        : NSLocalizedString(@"Total N/A", "stats total");
+    [fRatioAllField setStringValue: totalRatioString];
     
     [fTimeField setStringValue: [self timeString: statsSession.secondsActive]];
     [fTimeAllField setStringValue: [[self timeString: statsAll.secondsActive]