diff --git a/js/beestat/math.js b/js/beestat/math.js
new file mode 100644
index 0000000..9de3016
--- /dev/null
+++ b/js/beestat/math.js
@@ -0,0 +1,41 @@
+beestat.math = {};
+
+/**
+ * Get a linear trendline from a set of data.
+ *
+ * @param {Object} data The data; at least two points required.
+ *
+ * @return {Object} The slope and intercept of the trendline.
+ */
+beestat.math.get_linear_trendline = function(data) {
+  // Requires at least two points.
+  if (Object.keys(data).length < 2) {
+    return null;
+  }
+
+  var sum_x = 0;
+  var sum_y = 0;
+  var sum_xy = 0;
+  var sum_x_squared = 0;
+  var n = 0;
+
+  for (var x in data) {
+    x = parseFloat(x);
+    var y = parseFloat(data[x]);
+
+    sum_x += x;
+    sum_y += y;
+    sum_xy += (x * y);
+    sum_x_squared += Math.pow(x, 2);
+    n++;
+  }
+
+  var slope = ((n * sum_xy) - (sum_x * sum_y)) /
+    ((n * sum_x_squared) - (Math.pow(sum_x, 2)));
+  var intercept = ((sum_y) - (slope * sum_x)) / (n);
+
+  return {
+    'slope': slope,
+    'intercept': intercept
+  };
+};
diff --git a/js/component/card/temperature_profiles.js b/js/component/card/temperature_profiles.js
index 57c4920..dd7bea8 100644
--- a/js/component/card/temperature_profiles.js
+++ b/js/component/card/temperature_profiles.js
@@ -138,7 +138,7 @@ beestat.component.card.temperature_profiles.prototype.get_data_ = function() {
         }
 
         profile.deltas = deltas_converted;
-        var linear_trendline = this.get_linear_trendline_(profile.deltas);
+        var linear_trendline = beestat.math.get_linear_trendline(profile.deltas);
 
         var min_max_keys = Object.keys(profile.deltas);
 
@@ -215,49 +215,6 @@ beestat.component.card.temperature_profiles.prototype.get_data_ = function() {
   return data;
 };
 
-/**
- * Get a linear trendline from a set of data.
- *
- * IMPORTANT: This exists in the profile already but it's wrong to use it
- * directly as it's not right for Celsius.
- *
- * @param {Object} data The data; at least two points required.
- *
- * @return {Object} The slope and intercept of the trendline.
- */
-beestat.component.card.temperature_profiles.prototype.get_linear_trendline_ = function(data) {
-  // Requires at least two points.
-  if (Object.keys(data).length < 2) {
-    return null;
-  }
-
-  var sum_x = 0;
-  var sum_y = 0;
-  var sum_xy = 0;
-  var sum_x_squared = 0;
-  var n = 0;
-
-  for (var x in data) {
-    x = parseFloat(x);
-    var y = parseFloat(data[x]);
-
-    sum_x += x;
-    sum_y += y;
-    sum_xy += (x * y);
-    sum_x_squared += Math.pow(x, 2);
-    n++;
-  }
-
-  var slope = ((n * sum_xy) - (sum_x * sum_y)) /
-    ((n * sum_x_squared) - (Math.pow(sum_x, 2)));
-  var intercept = ((sum_y) - (slope * sum_x)) / (n);
-
-  return {
-    'slope': slope,
-    'intercept': intercept
-  };
-};
-
 /**
  * Get the title of the card.
  *
diff --git a/js/component/modal/temperature_profiles_info.js b/js/component/modal/temperature_profiles_info.js
index bc1863d..a6e8b1a 100644
--- a/js/component/modal/temperature_profiles_info.js
+++ b/js/component/modal/temperature_profiles_info.js
@@ -29,13 +29,29 @@ beestat.component.modal.temperature_profiles_info.prototype.decorate_contents_ =
     'resist'
   ].forEach(function(type) {
     if (thermostat.profile.temperature[type] !== null) {
+      const profile = thermostat.profile.temperature[type];
+
+      // Convert the data to Celsius if necessary
+      const deltas_converted = {};
+      for (let key in profile.deltas) {
+        deltas_converted[beestat.temperature({'temperature': key})] =
+          beestat.temperature({
+            'temperature': (profile.deltas[key]),
+            'delta': true,
+            'round': 3
+          });
+      }
+
+      profile.deltas = deltas_converted;
+      const linear_trendline = beestat.math.get_linear_trendline(profile.deltas);
+
       fields.push({
         'name': beestat.series['indoor_' + type + '_delta'].name,
         'value':
           'Slope = ' +
-          thermostat.profile.temperature[type].linear_trendline.slope +
+          linear_trendline.slope.toFixed(4) +
           '<br/>Intercept = ' +
-          thermostat.profile.temperature[type].linear_trendline.intercept
+          linear_trendline.intercept.toFixed(4) + beestat.setting('units.temperature')
       });
     }
   });
diff --git a/js/js.php b/js/js.php
index 3b29d3e..3acf3b9 100755
--- a/js/js.php
+++ b/js/js.php
@@ -49,6 +49,7 @@ if($setting->get('environment') === 'dev' || $setting->get('environment') === 'd
   echo '<script src="/js/beestat/address.js"></script>' . PHP_EOL;
   echo '<script src="/js/beestat/affiliate.js"></script>' . PHP_EOL;
   echo '<script src="/js/beestat/date.js"></script>' . PHP_EOL;
+  echo '<script src="/js/beestat/math.js"></script>' . PHP_EOL;
 
   // Layer
   echo '<script src="/js/layer.js"></script>' . PHP_EOL;