diff --git a/scripts/jantoran.py b/scripts/jantoran.py
index 1c27e16..529d3ad 100755
--- a/scripts/jantoran.py
+++ b/scripts/jantoran.py
@@ -41,11 +41,15 @@ def extract(p, s):
   print("done")
 
 def analyze_failure(s):
-  print(f"rate,duration")
-  for k, v in s['failure'].items():
-    rate = round(1000 / k)
-    for e in v:
-      print(f"{rate},{e}")
+  with open('jan_failure.csv', 'w') as f:
+    f.write(f"rate,duration,ecdf\n")
+    for k, v in s['failure'].items():
+      v = sorted(v)
+      total = len(v)
+      rate = round(1000 / k)
+      for idx,e in enumerate(v,start=1):
+        if e == 90: break
+        f.write(f"{rate},{e},{idx/total}\n")
 
 def analyze(s):
   print("analyzing...")