diff --git a/src/androidTest/java/de/dennisguse/opentracks/util/EGM2008UtilsTest.java b/src/androidTest/java/de/dennisguse/opentracks/util/EGM2008UtilsTest.java
index f36b42c8a..242ef4d8e 100644
--- a/src/androidTest/java/de/dennisguse/opentracks/util/EGM2008UtilsTest.java
+++ b/src/androidTest/java/de/dennisguse/opentracks/util/EGM2008UtilsTest.java
@@ -142,7 +142,7 @@ public class EGM2008UtilsTest {
     }
 
     @Test
-    public void data_Berlin() throws IOException {
+    public void data_Berlin_Germany_() throws IOException {
         // given
         TrackPoint trackPoint = new TrackPoint(TrackPoint.Type.TRACKPOINT, Instant.ofEpochMilli(0));
         trackPoint.setLatitude(52.530644);
@@ -157,7 +157,7 @@ public class EGM2008UtilsTest {
     }
 
     @Test
-    public void data_Berlin_Caching() throws IOException {
+    public void data_Berlin_Germany_Caching() throws IOException {
         // given
         TrackPoint trackPoint1 = new TrackPoint(TrackPoint.Type.TRACKPOINT, Instant.ofEpochMilli(0));
         trackPoint1.setLatitude(52.530644);
@@ -176,6 +176,22 @@ public class EGM2008UtilsTest {
         assertNotEquals(altitude_egm2008.correctAltitude(trackPoint1.getLocation()), altitude_egm2008.correctAltitude(trackPoint2.getLocation()), 0.0001);
     }
 
+    @Test
+    public void data_Seattle_USA() throws IOException {
+        // given
+        TrackPoint trackPoint = new TrackPoint(TrackPoint.Type.TRACKPOINT, Instant.ofEpochMilli(0));
+
+        trackPoint.setLatitude(47.63153);
+        trackPoint.setLongitude(-122.30938);
+        trackPoint.setAltitude(0);
+
+        // when
+        EGM2008Utils.EGM2008Correction altitude_egm2008 = EGM2008Utils.createCorrection(context, trackPoint.getLocation());
+
+        // then
+        assertEquals(22.99, altitude_egm2008.correctAltitude(trackPoint.getLocation()), MAX_BILINEAR_ERROR);
+    }
+
     @Test
     public void data_MaxUndulation() throws IOException {
         // given
@@ -191,6 +207,7 @@ public class EGM2008UtilsTest {
         assertEquals(-85.824, altitude_egm2008.correctAltitude(trackPoint.getLocation()), MAX_BILINEAR_ERROR);
     }
 
+
     @Test
     public void getIndices() {
         TrackPoint trackPoint = new TrackPoint(TrackPoint.Type.TRACKPOINT, Instant.ofEpochMilli(0));
@@ -208,7 +225,7 @@ public class EGM2008UtilsTest {
 
         trackPoint.setLatitude(-90);
         trackPoint.setLongitude(-180);
-        assertEquals(new EGM2008Utils.Indices(2160, 0), EGM2008Utils.getIndices(trackPoint.getLocation()));
+        assertEquals(new EGM2008Utils.Indices(2160, 2160), EGM2008Utils.getIndices(trackPoint.getLocation()));
     }
 
     @Test
diff --git a/src/main/java/de/dennisguse/opentracks/util/EGM2008Utils.java b/src/main/java/de/dennisguse/opentracks/util/EGM2008Utils.java
index 739a5f2b5..79f370288 100644
--- a/src/main/java/de/dennisguse/opentracks/util/EGM2008Utils.java
+++ b/src/main/java/de/dennisguse/opentracks/util/EGM2008Utils.java
@@ -65,7 +65,7 @@ public class EGM2008Utils {
         if (location.getLongitude() >= 0) {
             longitude = location.getLongitude();
         } else {
-            longitude = 180 + Math.abs(location.getLongitude());
+            longitude = 360 + location.getLongitude();
         }
         int longitudeIndex = (int) (longitude * RESOLUTION_IN_MINUTES);
 
@@ -172,5 +172,13 @@ public class EGM2008Utils {
         public int hashCode() {
             return Objects.hash(latitudeIndex, longitudeIndex);
         }
+
+        @Override
+        public String toString() {
+            return "Indices{" +
+                    "latitudeIndex=" + latitudeIndex +
+                    ", longitudeIndex=" + longitudeIndex +
+                    '}';
+        }
     }
 }