diff -r 8f03f0dc3065 -r e10a9b2fd35a marking/drumb_test2.scala
--- a/marking/drumb_test2.scala	Wed Jan 11 14:42:46 2017 +0000
+++ b/marking/drumb_test2.scala	Sat Jan 21 00:43:35 2017 +0000
@@ -5,10 +5,21 @@
 import ExecutionContext.Implicits.global
 import scala.language.postfixOps 
 
+val urban_prices = List(List(Some(71.539941), None), 
+                        List(Some(76.974614), None), 
+                        List(Some(65.226685), Some(6.35)), 
+                        List(Some(78.354649), Some(12.241)), 
+                        List(Some(85.517645), Some(38.188)))
+
+val urban_deltas = List(List(Some(0.07596697626574789), None), 
+                        List(Some(-0.152620823795232), None), 
+                        List(Some(0.20126676681483952), Some(0.9277165354330709)), 
+                        List(Some(0.09141762603007778), Some(2.119679764725104)))
+
+
 lazy val f = Future {
-  assert(get_prices(List("BIDU"), 2004 to 2008) == List(List(None), List(None), 
-                                                        List(Some(6.35)), List(Some(12.241)), 
-                                                        List(Some(38.188))))
+  //assert(get_deltas(urban_prices) == urban_deltas)
+  assert (get_deltas(get_prices(List("IBM", "BIDU"), 2004 to 2008)) == urban_deltas)
 }