diff --git a/Environment/Service/Controllers/ReadingsController.cs b/Environment/Service/Controllers/ReadingsController.cs
index 6f00a2e..da9b8f2 100644
--- a/Environment/Service/Controllers/ReadingsController.cs
+++ b/Environment/Service/Controllers/ReadingsController.cs
@@ -32,4 +32,10 @@ public class ReadingsController(Database database) : ControllerBase
 
         return Ok(recentReadings);
     }
+
+    [HttpGet("history-grouped")]
+    public async Task<ActionResult<List<ReadingsGrouped>>> GetHistoryGrouped(DateTimeOffset start, DateTimeOffset end, int bucketMinutes = 5)
+    {
+        return (await database.GetReadingsHistoryGrouped(start, end, bucketMinutes)).ToList();
+    }
 }
\ No newline at end of file
diff --git a/Environment/Service/Data/Database.cs b/Environment/Service/Data/Database.cs
index d08e882..a58fd8f 100644
--- a/Environment/Service/Data/Database.cs
+++ b/Environment/Service/Data/Database.cs
@@ -47,7 +47,7 @@ public class Database(IConfiguration configuration)
     {
         await using var connection = CreateConnection();
 
-        var query = ResourceReader.GetString("ChrisKaczor.HomeMonitor.Environment.Service.Data.Queries.CreateReading.sql");
+        var query = ResourceReader.GetString("ChrisKaczor.HomeMonitor.Environment.Service.Data.Queries.CreateReading.psql");
 
         await connection.QueryAsync(query, message);
     }
@@ -56,8 +56,17 @@ public class Database(IConfiguration configuration)
     {
         await using var connection = CreateConnection();
 
-        var query = ResourceReader.GetString("ChrisKaczor.HomeMonitor.Environment.Service.Data.Queries.GetRecentReadings.sql");
+        var query = ResourceReader.GetString("ChrisKaczor.HomeMonitor.Environment.Service.Data.Queries.GetRecentReadings.psql");
 
         return await connection.QueryAsync<Readings>(query).ConfigureAwait(false);
     }
+
+    public async Task<IEnumerable<ReadingsGrouped>> GetReadingsHistoryGrouped(DateTimeOffset start, DateTimeOffset end, int bucketMinutes)
+    {
+        await using var connection = CreateConnection();
+
+        var query = ResourceReader.GetString("ChrisKaczor.HomeMonitor.Environment.Service.Data.Queries.GetReadingsHistoryGrouped.psql");
+
+        return await connection.QueryAsync<ReadingsGrouped>(query, new { Start = start, End = end, BucketMinutes = bucketMinutes }).ConfigureAwait(false);
+    }
 }
\ No newline at end of file
diff --git a/Environment/Service/Data/Queries/CreateReading.sql b/Environment/Service/Data/Queries/CreateReading.psql
similarity index 100%
rename from Environment/Service/Data/Queries/CreateReading.sql
rename to Environment/Service/Data/Queries/CreateReading.psql
diff --git a/Environment/Service/Data/Queries/GetReadingsHistoryGrouped.psql b/Environment/Service/Data/Queries/GetReadingsHistoryGrouped.psql
new file mode 100644
index 0000000..0701758
--- /dev/null
+++ b/Environment/Service/Data/Queries/GetReadingsHistoryGrouped.psql
@@ -0,0 +1,20 @@
+SELECT
+  time_bucket('15 minute', time) AS bucket,
+  name,
+  ROUND(avg(temperature), 2) AS averageTemperature,
+  ROUND(avg(pressure), 2) AS averagePressure,
+  ROUND(avg(humidity), 2) AS averageHumidity,
+  ROUND(avg(luminance), 2) AS averageLuminance,
+  ROUND(avg(gas_resistance), 2) AS averageGasResistance,
+  ROUND(avg(color_temperature), 2) AS averageColorTemperature,
+  ROUND(avg(air_quality_index), 2) AS averageAirQualityIndex
+FROM
+  reading
+WHERE
+  time BETWEEN @Start AND @End
+GROUP BY
+  bucket,
+  name
+ORDER BY
+  bucket ASC,
+  name;
diff --git a/Environment/Service/Data/Queries/GetRecentReadings.sql b/Environment/Service/Data/Queries/GetRecentReadings.psql
similarity index 100%
rename from Environment/Service/Data/Queries/GetRecentReadings.sql
rename to Environment/Service/Data/Queries/GetRecentReadings.psql
diff --git a/Environment/Service/Data/Schema/1-Initial Schema.sql b/Environment/Service/Data/Schema/1-Initial Schema.psql
similarity index 100%
rename from Environment/Service/Data/Schema/1-Initial Schema.sql
rename to Environment/Service/Data/Schema/1-Initial Schema.psql
diff --git a/Environment/Service/Environment.http b/Environment/Service/Environment.http
index 6c23683..4291ce4 100644
--- a/Environment/Service/Environment.http
+++ b/Environment/Service/Environment.http
@@ -7,3 +7,8 @@ Accept: application/json
 
 GET {{Environment_HostAddress}}/readings/recent?tz=America/New_York
 Accept: application/json
+
+###
+
+GET {{Environment_HostAddress}}/readings/history-grouped?start=2024-02-02T06:00&end=2024-02-02T08:00&bucketMinutes=15
+Accept: application/json
\ No newline at end of file
diff --git a/Environment/Service/MessageHandler.cs b/Environment/Service/MessageHandler.cs
index 2a22964..027a41b 100644
--- a/Environment/Service/MessageHandler.cs
+++ b/Environment/Service/MessageHandler.cs
@@ -1,9 +1,9 @@
-using System.Text.Json;
-using ChrisKaczor.HomeMonitor.Environment.Service.Data;
+using ChrisKaczor.HomeMonitor.Environment.Service.Data;
 using ChrisKaczor.HomeMonitor.Environment.Service.Models.Indoor;
 using Microsoft.AspNetCore.SignalR.Client;
 using MQTTnet;
 using MQTTnet.Client;
+using System.Text.Json;
 
 namespace ChrisKaczor.HomeMonitor.Environment.Service;
 
@@ -22,8 +22,6 @@ public class MessageHandler : IHostedService
         _configuration = configuration;
         _database = database;
 
-        _database.EnsureDatabase();
-
         _topic = _configuration["Mqtt:Topic"] ?? string.Empty;
 
         if (string.IsNullOrEmpty(_topic))
diff --git a/Environment/Service/Models/ReadingsGrouped.cs b/Environment/Service/Models/ReadingsGrouped.cs
new file mode 100644
index 0000000..5c3d9bb
--- /dev/null
+++ b/Environment/Service/Models/ReadingsGrouped.cs
@@ -0,0 +1,25 @@
+using JetBrains.Annotations;
+
+namespace ChrisKaczor.HomeMonitor.Environment.Service.Models;
+
+[PublicAPI]
+public class ReadingsGrouped
+{
+    public DateTimeOffset Bucket { get; set; }
+
+    public string? Name { get; set; }
+
+    public decimal AverageTemperature { get; set; }
+
+    public decimal AveragePressure { get; set; }
+
+    public decimal AverageHumidity { get; set; }
+
+    public decimal AverageLuminance { get; set; }
+
+    public decimal AverageGasResistance { get; set; }
+
+    public decimal AverageColorTemperature { get; set; }
+
+    public decimal AverageAirQualityIndex { get; set; }
+}
\ No newline at end of file
diff --git a/Environment/Service/Program.cs b/Environment/Service/Program.cs
index 5c7901b..ec68c3d 100644
--- a/Environment/Service/Program.cs
+++ b/Environment/Service/Program.cs
@@ -25,6 +25,9 @@ public static class Program
 
         app.MapControllers();
 
+        var database = app.Services.GetRequiredService<Database>();
+        database.EnsureDatabase();
+
         app.Run();
     }
 }
\ No newline at end of file
diff --git a/Environment/Service/Service.csproj b/Environment/Service/Service.csproj
index a337ca3..07fe0a0 100644
--- a/Environment/Service/Service.csproj
+++ b/Environment/Service/Service.csproj
@@ -10,15 +10,17 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <None Remove="Data\Queries\CreateReading.sql" />
-    <None Remove="Data\Queries\GetRecentReadings.sql" />
-    <None Remove="Data\Schema\1-Initial Schema.sql" />
+    <None Remove="Data\Queries\CreateReading.psql" />
+    <None Remove="Data\Queries\GetReadingsHistoryGrouped.psql" />
+    <None Remove="Data\Queries\GetRecentReadings.psql" />
+    <None Remove="Data\Schema\1-Initial Schema.psql" />
   </ItemGroup>
 
   <ItemGroup>
-    <EmbeddedResource Include="Data\Queries\GetRecentReadings.sql" />
-    <EmbeddedResource Include="Data\Queries\CreateReading.sql" />
-    <EmbeddedResource Include="Data\Schema\1-Initial Schema.sql" />
+    <EmbeddedResource Include="Data\Queries\GetReadingsHistoryGrouped.psql" />
+    <EmbeddedResource Include="Data\Queries\GetRecentReadings.psql" />
+    <EmbeddedResource Include="Data\Queries\CreateReading.psql" />
+    <EmbeddedResource Include="Data\Schema\1-Initial Schema.psql" />
   </ItemGroup>
 
   <ItemGroup>