load: value.ValeurIndex - data[index - 1].ValeurIndex,

manifest.konnector

 {
-  "version": "0.2.2",
+  "version": "1.0.0",
   "name": "EGL",
   "type": "konnector",
   "language": "node",

package.json

 {
   "name": "egl",
-  "version": "0.2.2",
+  "version": "1.0.0",
   "description": "",
   "repository": {
     "type": "git",

src/index.js

@@ -239,9 +239,9 @@ function format(response) {
   log('info', 'filtered size is : ' + dataLen)
   const mapData = data.map((value, index) => {
     const time = moment(value.DateReleve, moment.ISO_8601)
-    if (index + 1 < dataLen) {
+    if (index !== 0 && index < dataLen) {
       return {
-        load: data[index + 1].ValeurIndex - value.ValeurIndex,
+        load: value.ValeurIndex - data[index - 1].ValeurIndex,
         year: parseInt(time.format('YYYY')),
         month: parseInt(time.format('M')),
         day: parseInt(time.format('D')),