diff --git a/src/components/state-history-chart-line.html b/src/components/state-history-chart-line.html
index 009234f8cf..c0d714f966 100644
--- a/src/components/state-history-chart-line.html
+++ b/src/components/state-history-chart-line.html
@@ -147,11 +147,17 @@
         dataTable.addColumn({ type: 'datetime', id: 'Time' });
 
         function pushData(values, noInterpolationValues) {
+          var timestamp = values[0];
+          if (timestamp > endTime) {
+            // Drop datapoints that are after the requested endTime. This could happen if
+            // endTime is "now" and client time is not in sync with server time.
+            return;
+          }
           if (prevValues && noInterpolationValues) {
             // if we have to prevent interpolation, we add an old value for each
             // value that should not be interpolated at the same time that our new
             // line will be published.
-            data.push([values[0]].concat(prevValues.slice(1).map(
+            data.push([timestamp].concat(prevValues.slice(1).map(
               function (val, index) {
                 return noInterpolationValues[index] ? val : null;
               })));
@@ -160,44 +166,7 @@
           prevValues = values;
         }
 
-        if (domain === 'thermostat') {
-          // We differentiate between thermostats that have a target temperature
-          // range versus ones that have just a target temperature
-          hasTargetRange = states.reduce(
-            function (cum, cur) {
-              return cum || cur.attributes.target_temp_high !== cur.attributes.target_temp_low;
-            }, false);
-
-          dataTable.addColumn('number', name + ' current temperature');
-
-          if (hasTargetRange) {
-            dataTable.addColumn('number', name + ' target temperature high');
-            dataTable.addColumn('number', name + ' target temperature low');
-
-            noInterpolations = [false, true, true];
-
-            processState = function (state) {
-              var curTemp = saveParseFloat(state.attributes.current_temperature);
-              var targetHigh = saveParseFloat(state.attributes.target_temp_high);
-              var targetLow = saveParseFloat(state.attributes.target_temp_low);
-              pushData(
-                [new Date(state.last_updated), curTemp, targetHigh, targetLow],
-                noInterpolations);
-            };
-          } else {
-            dataTable.addColumn('number', name + ' target temperature');
-
-            noInterpolations = [false, true];
-
-            processState = function (state) {
-              var curTemp = saveParseFloat(state.attributes.current_temperature);
-              var target = saveParseFloat(state.attributes.temperature);
-              pushData([new Date(state.last_updated), curTemp, target], noInterpolations);
-            };
-          }
-
-          states.forEach(processState);
-        } else if (domain === 'climate') {
+        if (domain === 'thermostat' || domain === 'climate') {
           // We differentiate between thermostats that have a target temperature
           // range versus ones that have just a target temperature
           hasTargetRange = states.reduce(
diff --git a/src/components/state-history-chart-timeline.html b/src/components/state-history-chart-timeline.html
index 7f61662d59..4ed7c0f101 100644
--- a/src/components/state-history-chart-timeline.html
+++ b/src/components/state-history-chart-timeline.html
@@ -112,6 +112,12 @@ Polymer({
       entityDisplay = window.hassUtil.computeStateName(stateInfo[0]);
 
       stateInfo.forEach(function (state) {
+        var timeStamp = new Date(state.last_changed);
+        if (timeStamp > endTime) {
+          // Drop datapoints that are after the requested endTime. This could happen if
+          // endTime is "now" and client time is not in sync with server time.
+          return;
+        }
         if (prevState !== null && state.state !== prevState) {
           newLastChanged = new Date(state.last_changed);
 
diff --git a/src/data/ha-state-history-data.html b/src/data/ha-state-history-data.html
index c496162d2c..95a0b38026 100644
--- a/src/data/ha-state-history-data.html
+++ b/src/data/ha-state-history-data.html
@@ -6,7 +6,7 @@
   var DATE_CACHE = {};
   var RECENT_CACHE = {};
 
-  function computeHistory(stateHistory, endTime) {
+  function computeHistory(stateHistory) {
     var lineChartDevices = {};
     var timelineDevices = [];
     var unitStates;
@@ -23,14 +23,6 @@
         return;
       }
 
-      // Duplicate the last state to the selected endTime so the chart expands
-      // to the end of the selected time. (If no additional state changes were
-      // found, the state was still the last state as of the end time.
-      var lastState = Object.assign({}, stateInfo[stateInfo.length - 1]);
-      lastState.last_changed = endTime;
-      lastState.last_updated = endTime;
-      stateInfo.push(lastState);
-
       stateWithUnit = stateInfo.find(
         function (state) { return 'unit_of_measurement' in state.attributes; });
 
@@ -145,7 +137,7 @@
 
       var prom = this.hass.callApi('GET', url).then(
         function (stateHistory) {
-          return computeHistory(stateHistory, Date.now());
+          return computeHistory(stateHistory);
         },
         function () {
           RECENT_CACHE[entityId] = false;
@@ -166,7 +158,7 @@
       if (!DATE_CACHE[filter]) {
         DATE_CACHE[filter] = this.hass.callApi('GET', 'history/period/' + filter).then(
           function (stateHistory) {
-            return computeHistory(stateHistory, endTime);
+            return computeHistory(stateHistory);
           },
           function () {
             DATE_CACHE[filter] = false;