diff --git a/src/main.rs b/src/main.rs
index ae8eea6..863e3d7 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -89,12 +89,13 @@ fn aggregate_values(conn: &mut PooledConn, date: NaiveDate) -> Result<(), Box<dy
         Sensor::new("maison".to_string(), "bureau".to_string(), "tvoc".to_string())
     ];
 
+    let average_duration = 15;
     for sensor in &sensors {
         let mut current_time = start_time;
 
         while current_time <= end_time {
             let start_time_loop = current_time.to_string();
-            let end_time_loop = (current_time + Duration::minutes(29) + Duration::seconds(59)).to_string();
+            let end_time_loop = (current_time + Duration::minutes(average_duration - 1) + Duration::seconds(59)).to_string();
 
             let query = format!("SELECT * FROM donnees WHERE service = '{}' AND capteur = '{}' AND type = '{}' AND (date_donnee BETWEEN '{}' AND '{}');", sensor.service, sensor.capteur, sensor.type_donnee, start_time_loop, end_time_loop);
             let selected_rows: Vec<Row> = conn.query(query)?;
@@ -112,7 +113,7 @@ fn aggregate_values(conn: &mut PooledConn, date: NaiveDate) -> Result<(), Box<dy
 
             if count > 1 {
                 let average = value / count;
-                let entry_date = current_time + Duration::minutes(15);
+                let entry_date = current_time + (Duration::minutes(average_duration) / 2);
                 let donnee = Donnee {
                     id: 0,
                     service: sensor.service.to_string(),
@@ -127,7 +128,7 @@ fn aggregate_values(conn: &mut PooledConn, date: NaiveDate) -> Result<(), Box<dy
                 let query = "DELETE FROM donnees WHERE id IN (".to_owned() + &*ids.join(", ") + ");";
                 let _: Vec<Row> = conn.query(query)?;
             }
-            current_time = current_time + Duration::minutes(15);
+            current_time = current_time + Duration::minutes(average_duration);
         }
     }