diff --git a/concurrencydifference.txt b/concurrencydifference.txt
new file mode 100644
index 0000000..ec17b43
--- /dev/null
+++ b/concurrencydifference.txt
@@ -0,0 +1,15 @@
+Earlier development stage:
+[dgurney@desktop temp]$ time png_noc -n 100 -w 1920 -h 1080
+
+real	0m49.048s
+user	0m48.905s
+sys	0m0.243s
+
+v1.0.4:
+[dgurney@desktop temp]$ time pngen -a 100 -w 1920 -h 1080
+Generating 100 1920x1080 PNG files...
+
+real	0m17.734s
+user	0m50.871s
+sys	0m0.263s
+