diff --git a/bin/oref0-autosens-history.js b/bin/oref0-autosens-history.js
index 45babff1a..bf51ccdd6 100755
--- a/bin/oref0-autosens-history.js
+++ b/bin/oref0-autosens-history.js
@@ -179,39 +179,4 @@ function convertBasal(item)
       //"minutes": Math.round(item.timeAsSeconds / 60),
       "rate": item.value
   };
-}
-
-// From https://gist.github.com/IceCreamYou/6ffa1b18c4c8f6aeaad2
-// Returns the value at a given percentile in a sorted numeric array.
-// "Linear interpolation between closest ranks" method
-function percentile(arr, p) {
-    if (arr.length === 0) return 0;
-    if (typeof p !== 'number') throw new TypeError('p must be a number');
-    if (p <= 0) return arr[0];
-    if (p >= 1) return arr[arr.length - 1];
-
-    var index = arr.length * p,
-        lower = Math.floor(index),
-        upper = lower + 1,
-        weight = index % 1;
-
-    if (upper >= arr.length) return arr[lower];
-    return arr[lower] * (1 - weight) + arr[upper] * weight;
-}
-
-// Returns the percentile of the given value in a sorted numeric array.
-function percentRank(arr, v) {
-    if (typeof v !== 'number') throw new TypeError('v must be a number');
-    for (var i = 0, l = arr.length; i < l; i++) {
-        if (v <= arr[i]) {
-            while (i < l && v === arr[i]) i++;
-            if (i === 0) return 0;
-            if (v !== arr[i-1]) {
-                i += (v - arr[i-1]) / (arr[i] - arr[i-1]);
-            }
-            return i / l;
-        }
-    }
-    return 1;
-}
-
+}
\ No newline at end of file
diff --git a/lib/autotune/index.js b/lib/autotune/index.js
index 06fc207a4..4691d2e8a 100644
--- a/lib/autotune/index.js
+++ b/lib/autotune/index.js
@@ -1,3 +1,5 @@
+var percentile = require('../percentile')
+
 // does three things - tunes basals, ISF, and CSF
 
 function tuneAllTheThings (inputs) {
@@ -538,22 +540,3 @@ function tuneAllTheThings (inputs) {
 }
 
 exports = module.exports = tuneAllTheThings;
-
-// From https://gist.github.com/IceCreamYou/6ffa1b18c4c8f6aeaad2
-// Returns the value at a given percentile in a sorted numeric array.
-// "Linear interpolation between closest ranks" method
-function percentile(arr, p) {
-    if (arr.length === 0) return 0;
-    if (typeof p !== 'number') throw new TypeError('p must be a number');
-    if (p <= 0) return arr[0];
-    if (p >= 1) return arr[arr.length - 1];
-
-    var index = arr.length * p,
-        lower = Math.floor(index),
-        upper = lower + 1,
-        weight = index % 1;
-
-    if (upper >= arr.length) return arr[lower];
-    return arr[lower] * (1 - weight) + arr[upper] * weight;
-}
-
diff --git a/lib/determine-basal/autosens.js b/lib/determine-basal/autosens.js
index 3591fc8ea..bf178b1c7 100644
--- a/lib/determine-basal/autosens.js
+++ b/lib/determine-basal/autosens.js
@@ -4,6 +4,7 @@ var find_insulin = require('../iob/history');
 var isf = require('../profile/isf');
 var find_meals = require('../meal/history');
 var tz = require('moment-timezone');
+var percentile = require('../percentile');
 
 function detectSensitivity(inputs) {
 
@@ -422,24 +423,6 @@ function detectSensitivity(inputs) {
 }
 module.exports = detectSensitivity;
 
-// From https://gist.github.com/IceCreamYou/6ffa1b18c4c8f6aeaad2
-// Returns the value at a given percentile in a sorted numeric array.
-// "Linear interpolation between closest ranks" method
-function percentile(arr, p) {
-    if (arr.length === 0) return 0;
-    if (typeof p !== 'number') throw new TypeError('p must be a number');
-    if (p <= 0) return arr[0];
-    if (p >= 1) return arr[arr.length - 1];
-
-    var index = arr.length * p,
-        lower = Math.floor(index),
-        upper = lower + 1,
-        weight = index % 1;
-
-    if (upper >= arr.length) return arr[lower];
-    return arr[lower] * (1 - weight) + arr[upper] * weight;
-}
-
 function tempTargetRunning(temptargets_data, time) {
     // sort tempTargets by date so we can process most recent first
     try {
diff --git a/lib/iob/calculate.js b/lib/iob/calculate.js
index 3c9f8f85a..31498785c 100644
--- a/lib/iob/calculate.js
+++ b/lib/iob/calculate.js
@@ -136,12 +136,10 @@ function iobCalcExponential(treatment, minsAgo, dia, peak, profile) {
         //console.error('DIA: ' + dia + ' minsAgo: ' + minsAgo + ' end: ' + end + ' peak: ' + peak + ' tau: ' + tau + ' a: ' + a + ' S: ' + S + ' activityContrib: ' + activityContrib + ' iobContrib: ' + iobContrib);
     }
 
-    var results = {
+    return {
         activityContrib: activityContrib,
         iobContrib: iobContrib        
     };
-
-    return results;
 }
 
 
diff --git a/lib/percentile.js b/lib/percentile.js
new file mode 100644
index 000000000..5e8b02049
--- /dev/null
+++ b/lib/percentile.js
@@ -0,0 +1,17 @@
+// From https://gist.github.com/IceCreamYou/6ffa1b18c4c8f6aeaad2
+// Returns the value at a given percentile in a sorted numeric array.
+// "Linear interpolation between closest ranks" method
+module.exports = function percentile(arr, p) {
+    if (arr.length === 0) return 0;
+    if (typeof p !== 'number') throw new TypeError('p must be a number');
+    if (p <= 0) return arr[0];
+    if (p >= 1) return arr[arr.length - 1];
+
+    var index = arr.length * p,
+        lower = Math.floor(index),
+        upper = lower + 1,
+        weight = index % 1;
+
+    if (upper >= arr.length) return arr[lower];
+    return arr[lower] * (1 - weight) + arr[upper] * weight;
+}
\ No newline at end of file