diff --git a/pkg/cmd/backtest.go b/pkg/cmd/backtest.go
index 3982aab5d..6ebd73a13 100644
--- a/pkg/cmd/backtest.go
+++ b/pkg/cmd/backtest.go
@@ -6,7 +6,6 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
-	"sort"
 	"strings"
 	"syscall"
 	"time"
@@ -697,7 +696,7 @@ func confirmation(s string) bool {
 	}
 }
 
-func getExchangeIntervals(ex types.Exchange) map[types.Interval]int {
+func getExchangeIntervals(ex types.Exchange) types.IntervalMap {
 	exCustom, ok := ex.(types.CustomIntervalProvider)
 	if ok {
 		return exCustom.SupportedInterval()
@@ -705,13 +704,6 @@ func getExchangeIntervals(ex types.Exchange) map[types.Interval]int {
 	return types.SupportedIntervals
 }
 
-func sortIntervals(intervals []types.Interval) types.IntervalSlice {
-	sort.Slice(intervals, func(i, j int) bool {
-		return intervals[i].Duration() < intervals[j].Duration()
-	})
-	return intervals
-}
-
 func sync(ctx context.Context, userConfig *bbgo.Config, backtestService *service.BacktestService, sourceExchanges map[types.ExchangeName]types.Exchange, syncFrom, syncTo time.Time) error {
 	for _, symbol := range userConfig.Backtest.Symbols {
 		for _, sourceExchange := range sourceExchanges {
@@ -722,11 +714,7 @@ func sync(ctx context.Context, userConfig *bbgo.Config, backtestService *service
 			}
 
 			// sort intervals
-			var intervals types.IntervalSlice
-			for interval := range supportIntervals {
-				intervals = append(intervals, interval)
-			}
-
+			var intervals = supportIntervals.Slice()
 			intervals.Sort()
 
 			for _, interval := range intervals {
diff --git a/pkg/types/interval.go b/pkg/types/interval.go
index 054db6d5f..338006193 100644
--- a/pkg/types/interval.go
+++ b/pkg/types/interval.go
@@ -142,7 +142,17 @@ func ParseInterval(input Interval) int {
 	return t
 }
 
-var SupportedIntervals = map[Interval]int{
+type IntervalMap map[Interval]int
+
+func (m IntervalMap) Slice() (slice IntervalSlice) {
+	for interval := range m {
+		slice = append(slice, interval)
+	}
+
+	return slice
+}
+
+var SupportedIntervals = IntervalMap{
 	Interval1s:  1,
 	Interval1m:  1 * 60,
 	Interval3m:  3 * 60,