diff --git a/src/saving_test.go b/src/saving_test.go
new file mode 100644
index 0000000..893e877
--- /dev/null
+++ b/src/saving_test.go
@@ -0,0 +1,43 @@
+// saving_test.go
+package main
+
+import (
+	"math/rand"
+	"testing"
+)
+
+func BenchmarkCsvSavingOnlySum(b *testing.B) {
+	data := make([]StatForTime, 0)
+	keyMap := GetKeymap()
+	rnd := rand.New(rand.NewSource(42))
+	for i := 0; i < b.N; i++ {
+		var curStat StatForTime
+		curStat.Init()
+		for keyNum := range keyMap {
+			if rnd.Float32() > 0.7 {
+				curStat.keys[keyNum] = rnd.Intn(5000)
+			}
+		}
+		data = append(data, curStat)
+	}
+	b.ResetTimer()
+	SaveToCsvFile(data, keyMap, "/tmp/bla.csv", true)
+}
+
+func BenchmarkCsvSaving(b *testing.B) {
+	data := make([]StatForTime, 0)
+	keyMap := GetKeymap()
+	rnd := rand.New(rand.NewSource(42))
+	for i := 0; i < b.N; i++ {
+		var curStat StatForTime
+		curStat.Init()
+		for keyNum := range keyMap {
+			if rnd.Float32() > 0.7 {
+				curStat.keys[keyNum] = rnd.Intn(5000)
+			}
+		}
+		data = append(data, curStat)
+	}
+	b.ResetTimer()
+	SaveToCsvFile(data, keyMap, "/tmp/bla.csv", false)
+}