diff --git a/api/index.php b/api/index.php
index c6efe7f..4d048ae 100644
--- a/api/index.php
+++ b/api/index.php
@@ -50,7 +50,7 @@ function array_median($array) {
 }
 
 // Useful function
-function array_average($array) {
+function array_mean($array) {
   if (count($array) === 0) {
     return null;
   }
diff --git a/api/profile.php b/api/profile.php
index bb44362..22057ca 100644
--- a/api/profile.php
+++ b/api/profile.php
@@ -177,6 +177,16 @@ class profile extends cora\api {
       'heat' => [],
       'cool' => []
     ];
+    $runtime_seconds = [
+      'heat_1' => 0,
+      'heat_2' => 0,
+      'auxiliary_heat_1' => 0,
+      'auxiliary_heat_2' => 0,
+      'cool_1' => 0,
+      'cool_2' => 0
+    ];
+    $degree_days_baseline = 65;
+    $degree_days = [];
     $begin_runtime = [];
 
     while($current_timestamp <= $end_timestamp) {
@@ -213,22 +223,26 @@ class profile extends cora\api {
         // consistently represented instead of having to do this logic
         // throughout the generator.
         $runtime = [];
+        $degree_days_date = date('Y-m-d', $current_timestamp);
+        $degree_days_temperatures = [];
         while($row = $result->fetch_assoc()) {
           $timestamp = strtotime($row['timestamp']);
           $hour = date('G', $timestamp);
+          $date = date('Y-m-d', $timestamp);
 
-          if (
-            $ignore_solar_heating === true &&
-            $hour > 6 &&
-            $hour < 22
-          ) {
-            continue;
+          // Degree days
+          if($date !== $degree_days_date) {
+            $degree_days[] = (array_mean($degree_days_temperatures) / 10) - $degree_days_baseline;
+            $degree_days_date = $date;
+            $degree_days_temperatures = [];
           }
+          $degree_days_temperatures[] = $row['outdoor_temperature'];
 
           if($first_timestamp === null) {
             $first_timestamp = $row['timestamp'];
           }
 
+          // Normalizing heating and cooling a bit.
           if(
             $thermostat['system_type']['detected']['heat'] === 'compressor' ||
             $thermostat['system_type']['detected']['heat'] === 'geothermal'
@@ -255,6 +269,21 @@ class profile extends cora\api {
             $row['cool_2'] = 0;
           }
 
+          $runtime_seconds['heat_1'] += $row['heat_1'];
+          $runtime_seconds['heat_2'] += $row['heat_2'];
+          $runtime_seconds['auxiliary_heat_1'] += $row['auxiliary_heat_1'];
+          $runtime_seconds['auxiliary_heat_2'] += $row['auxiliary_heat_2'];
+          $runtime_seconds['cool_1'] += $row['cool_1'];
+          $runtime_seconds['cool_2'] += $row['cool_2'];
+
+          if (
+            $ignore_solar_heating === true &&
+            $hour > 6 &&
+            $hour < 22
+          ) {
+            continue;
+          }
+
           if (isset($runtime[$timestamp]) === false) {
             $runtime[$timestamp] = [];
           }
@@ -630,8 +659,6 @@ class profile extends cora\api {
       $current_timestamp += $five_minutes;
     }
 
-    // print_r($samples);
-
     // Process the samples
     $deltas_raw = [];
     foreach($samples as $sample) {
@@ -670,6 +697,18 @@ class profile extends cora\api {
         'heat' => null,
         'cool' => null
       ],
+      'degree_days' => [
+        'heat' => null,
+        'cool' => null
+      ],
+      'runtime' => [
+        'heat_1' => round($runtime_seconds['heat_1'] / 3600),
+        'heat_2' => round($runtime_seconds['heat_2'] / 3600),
+        'auxiliary_heat_1' => round($runtime_seconds['auxiliary_heat_1'] / 3600),
+        'auxiliary_heat_2' => round($runtime_seconds['auxiliary_heat_2'] / 3600),
+        'cool_1' => round($runtime_seconds['cool_1'] / 3600),
+        'cool_2' => round($runtime_seconds['cool_2'] / 3600),
+      ],
       'metadata' => [
         'generated_at' => date('c'),
         'duration' => round((time() - strtotime($first_timestamp)) / 86400),
@@ -730,11 +769,27 @@ class profile extends cora\api {
 
     foreach(['heat', 'cool'] as $type) {
       if(count($setpoints[$type]) > 0) {
-        $profile['setpoint'][$type] = round(array_average($setpoints[$type])) / 10;
+        $profile['setpoint'][$type] = round(array_mean($setpoints[$type])) / 10;
         $profile['metadata']['setpoint'][$type]['samples'] = count($setpoints[$type]);
       }
     }
 
+    // Heating and cooling degree days.
+    foreach($degree_days as $degree_day) {
+      if($degree_day < 0) {
+        $profile['degree_days']['cool'] += ($degree_day * -1);
+      } else {
+        $profile['degree_days']['heat'] += ($degree_day);
+      }
+    }
+    if ($profile['degree_days']['cool'] !== null) {
+      $profile['degree_days']['cool'] = round($profile['degree_days']['cool']);
+    }
+    if ($profile['degree_days']['heat'] !== null) {
+      $profile['degree_days']['heat'] = round($profile['degree_days']['heat']);
+    }
+
+
     return $profile;
   }
 
diff --git a/api/thermostat_group.php b/api/thermostat_group.php
index c045e6a..fe91530 100644
--- a/api/thermostat_group.php
+++ b/api/thermostat_group.php
@@ -17,6 +17,7 @@ class thermostat_group extends cora\crud {
       'generate_profiles',
       'generate_profile',
       'get_scores',
+      'get_metrics',
       'update_system_types'
     ],
     'public' => []
@@ -27,7 +28,8 @@ class thermostat_group extends cora\crud {
     'generate_temperature_profiles' => 604800, // 7 Days
     'generate_profile' => 604800, // 7 Days
     'generate_profiles' => 604800, // 7 Days
-    'get_scores' => 604800 // 7 Days
+    'get_scores' => 604800, // 7 Days
+    'get_metrics' => 604800 // 7 Days
   ];
 
   /**
@@ -75,6 +77,18 @@ class thermostat_group extends cora\crud {
         'heat' => null,
         'cool' => null
       ],
+      'degree_days' => [
+        'heat' => null,
+        'cool' => null
+      ],
+      'runtime' => [
+        'heat_1' => 0,
+        'heat_2' => 0,
+        'auxiliary_heat_1' => 0,
+        'auxiliary_heat_2' => 0,
+        'cool_1' => 0,
+        'cool_2' => 0
+      ],
       'metadata' => [
         'generated_at' => date('c'),
         'duration' => null,
@@ -151,6 +165,22 @@ class thermostat_group extends cora\crud {
           }
         }
       }
+
+      // Degree days.
+      if($profile['degree_days']['heat'] !== null) {
+        $group_profile['degree_days']['heat'] += $profile['degree_days']['heat'];
+      }
+      if($profile['degree_days']['cool'] !== null) {
+        $group_profile['degree_days']['cool'] += $profile['degree_days']['cool'];
+      }
+
+      // Runtime
+      $group_profile['runtime']['heat_1'] += $profile['runtime']['heat_1'];
+      $group_profile['runtime']['heat_2'] += $profile['runtime']['heat_2'];
+      $group_profile['runtime']['auxiliary_heat_1'] += $profile['runtime']['auxiliary_heat_1'];
+      $group_profile['runtime']['auxiliary_heat_2'] += $profile['runtime']['auxiliary_heat_2'];
+      $group_profile['runtime']['cool_1'] += $profile['runtime']['cool_1'];
+      $group_profile['runtime']['cool_2'] += $profile['runtime']['cool_2'];
     }
 
     // echo '<pre>';
@@ -497,6 +527,151 @@ class thermostat_group extends cora\crud {
     return $scores;
   }
 
+  /**
+   * Compare this thermostat_group to all other matching ones.
+   *
+   * @param array $attributes The attributes to compare to.
+   *
+   * @return array
+   */
+  public function get_metrics($type, $attributes) {
+    // All or none are required.
+    if(
+      (
+        isset($attributes['address_latitude']) === true ||
+        isset($attributes['address_longitude']) === true ||
+        isset($attributes['address_radius']) === true
+      ) &&
+      (
+        isset($attributes['address_latitude']) === false ||
+        isset($attributes['address_longitude']) === false ||
+        isset($attributes['address_radius']) === false
+      )
+    ) {
+      throw new Exception('If one of address_latitude, address_longitude, or address_radius are set, then all are required.');
+    }
+
+    // Pull these values out so they don't get queried; this comparison is done
+    // in PHP.
+    if(isset($attributes['address_radius']) === true) {
+      $address_latitude = $attributes['address_latitude'];
+      $address_longitude = $attributes['address_longitude'];
+      $address_radius = $attributes['address_radius'];
+
+      unset($attributes['address_latitude']);
+      unset($attributes['address_longitude']);
+      unset($attributes['address_radius']);
+    }
+
+    $metric_codes = [
+      'setpoint_heat',
+      'setpoint_cool'
+    ];
+
+    $metrics = [];
+    foreach($metric_codes as $metric_code) {
+      $metrics[$metric_code] = [
+        'values' => [],
+        'histogram' => [],
+        'standard_deviation' => null,
+        'median' => null
+      ];
+    }
+
+    $limit_start = 0;
+    $limit_count = 1000;
+
+    /**
+     * Selecting lots of rows can eventually run PHP out of memory, so chunk
+     * this up into several queries to avoid that.
+     */
+    do {
+      // Get all matching thermostat groups.
+      $other_thermostat_groups = $this->database->read(
+        'thermostat_group',
+        $attributes,
+        [], // columns
+        [], // order_by
+        [$limit_start, $limit_count] // limit
+      );
+
+      // Get all the scores from the other thermostat groups
+      foreach($other_thermostat_groups as $other_thermostat_group) {
+        // Only use profiles with at least a year of data
+        // Only use profiles generated in the past year
+        //
+        if(
+          $other_thermostat_group['profile']['metadata']['duration'] >= 365 &&
+          strtotime($other_thermostat_group['profile']['metadata']['generated_at']) > strtotime('-1 year')
+        ) {
+          // Skip thermostat_groups that are too far away.
+          if(
+            isset($address_radius) === true &&
+            $this->haversine_great_circle_distance(
+              $address_latitude,
+              $address_longitude,
+              $other_thermostat_group['address_latitude'],
+              $other_thermostat_group['address_longitude']
+            ) > $address_radius
+          ) {
+            continue;
+          }
+
+          // setpoint_heat
+          if($other_thermostat_group['profile']['setpoint']['heat'] !== null) {
+            $setpoint_heat = round($other_thermostat_group['profile']['setpoint']['heat']);
+            if(isset($metrics['setpoint_heat']['histogram'][$setpoint_heat]) === false) {
+              $metrics['setpoint_heat']['histogram'][$setpoint_heat] = 0;
+            }
+            $metrics['setpoint_heat']['histogram'][$setpoint_heat]++;
+            $metrics['setpoint_heat']['values'][] = $setpoint_heat;
+          }
+
+          // setpoint_cool
+          if($other_thermostat_group['profile']['setpoint']['cool'] !== null) {
+            $setpoint_cool = round($other_thermostat_group['profile']['setpoint']['cool']);
+            if(isset($metrics['setpoint_cool']['histogram'][$setpoint_cool]) === false) {
+              $metrics['setpoint_cool']['histogram'][$setpoint_cool] = 0;
+            }
+            $metrics['setpoint_cool']['histogram'][$setpoint_cool]++;
+            $metrics['setpoint_cool']['values'][] = $setpoint_cool;
+          }
+        }
+      }
+
+      $limit_start += $limit_count;
+    } while (count($other_thermostat_groups) === $limit_count);
+
+    // setpoint_heat
+    $metrics['setpoint_heat']['standard_deviation'] = round($this->standard_deviation(
+      $metrics['setpoint_heat']['values']
+    ), 2);
+    $metrics['setpoint_heat']['median'] = array_median($metrics['setpoint_heat']['values']);
+    unset($metrics['setpoint_heat']['values']);
+
+    // setpoint_cool
+    $metrics['setpoint_cool']['standard_deviation'] = round($this->standard_deviation(
+      $metrics['setpoint_cool']['values']
+    ), 2);
+    $metrics['setpoint_cool']['median'] = array_median($metrics['setpoint_cool']['values']);
+    unset($metrics['setpoint_cool']['values']);
+
+    return $metrics;
+  }
+
+  private function standard_deviation($array) {
+    $count = count($array);
+
+    $mean = array_mean($array);
+
+    $variance = 0;
+    foreach($array as $i) {
+      $variance += pow(($i - $mean), 2);
+    }
+
+    return sqrt($variance / $count);
+  }
+
   /**
    * Calculates the great-circle distance between two points, with the
    * Haversine formula.