diff --git a/decor/eta.go b/decor/eta.go
index 92b1bd4..0df4024 100644
--- a/decor/eta.go
+++ b/decor/eta.go
@@ -52,6 +52,9 @@
 //
 //	`wcc` optional WC config
 func MovingAverageETA(style TimeStyle, average ewma.MovingAverage, normalizer TimeNormalizer, wcc ...WC) Decorator {
+	if average == nil {
+		average = NewMedian()
+	}
 	d := &movingAverageETA{
 		WC:         initWC(wcc...),
 		producer:   chooseTimeProducer(style),