diff --git a/todo.txt b/todo.txt
index ac007f6b1..61246e6f1 100644
--- a/todo.txt
+++ b/todo.txt
@@ -31,6 +31,8 @@ a-b.go -> a_b.go renamer PR
 ! sliding window / moving average
   o port u/window*.mlr from mlrc to mlr (actually, fix mlr of course)
   o sliding-window averages into mapper step (C + Go)
+  i $ ~/git/johnkerl/scripts-math/stats/cump 0.9 3 100 > ccump.dat
+    $ pgr -nc -n -p -ms 5 ccump.dat &
 
 ! make a lag-by-n and lead-by-n