diff --git a/ops/aggregator.go b/ops/aggregator.go
index 1823b00..cae56d0 100644
--- a/ops/aggregator.go
+++ b/ops/aggregator.go
@@ -52,8 +52,33 @@ func (a *Aggregator) aggregate(product string, interval time.Duration) {
 	end := time.Now().Truncate(interval)
 	start := end.Add(-interval)
 
-	_, _ = a.Database.TradeService().
-		TradesInDateRange(product, start, end)
+	trades, err := a.Database.TradeService().TradesInDateRange(product, start, end)
+	if err != nil {
+		a.Logger.Info(`aggregator: database error="%v"`, err)
+		return
+	}
+
+	var agg tacitus.Aggregation
+	agg.Interval = int(interval)
+	agg.Product = product
+	agg.Timestamp = end
+
+	for _, t := range trades {
+		agg.Price = t.Price
+
+		if t.Buy {
+			agg.BuyVolume = agg.BuyVolume.Add(t.Size)
+			agg.BuyTransactions++
+		} else {
+			agg.SellVolume = agg.SellVolume.Add(t.Size)
+			agg.SellTransactions++
+		}
+	}
+
+	_, err = a.Database.AggregationService().CreateAggregation(agg)
+	if err != nil {
+		a.Logger.Info(`aggregator: database error="%v"`, err)
+	}
 }
 
 func (a *Aggregator) Stop() {