diff --git a/decor/counters.go b/decor/counters.go
index b7efdbe..0420275 100644
--- a/decor/counters.go
+++ b/decor/counters.go
@@ -38,20 +38,26 @@
 //	pairFmt="%f / %f"       output: "1.000000MB / 12.000000MB"
 //	pairFmt="% f / % f"     output: "1.000000 MB / 12.000000 MB"
 func Counters(unit interface{}, pairFmt string, wcc ...WC) Decorator {
-	if pairFmt == "" {
-		pairFmt = "% d / % d"
-	}
-	producer := func() DecorFunc {
-		switch unit.(type) {
-		case SizeB1024:
+	producer := func() DecorFunc {
+		switch unit.(type) {
+		case SizeB1024:
+			if pairFmt == "" {
+				pairFmt = "% d / % d"
+			}
 			return func(s Statistics) string {
 				return fmt.Sprintf(pairFmt, SizeB1024(s.Current), SizeB1024(s.Total))
 			}
 		case SizeB1000:
+			if pairFmt == "" {
+				pairFmt = "% d / % d"
+			}
 			return func(s Statistics) string {
 				return fmt.Sprintf(pairFmt, SizeB1000(s.Current), SizeB1000(s.Total))
 			}
 		default:
+			if pairFmt == "" {
+				pairFmt = "%d / %d"
+			}
 			return func(s Statistics) string {
 				return fmt.Sprintf(pairFmt, s.Current, s.Total)
 			}
@@ -94,20 +100,26 @@
 //	format="%f"    output: "12.000000MiB"
 //	format="% f"   output: "12.000000 MiB"
 func Total(unit interface{}, format string, wcc ...WC) Decorator {
-	if format == "" {
-		format = "% d"
-	}
-	producer := func() DecorFunc {
-		switch unit.(type) {
-		case SizeB1024:
+	producer := func() DecorFunc {
+		switch unit.(type) {
+		case SizeB1024:
+			if format == "" {
+				format = "% d"
+			}
 			return func(s Statistics) string {
 				return fmt.Sprintf(format, SizeB1024(s.Total))
 			}
 		case SizeB1000:
+			if format == "" {
+				format = "% d"
+			}
 			return func(s Statistics) string {
 				return fmt.Sprintf(format, SizeB1000(s.Total))
 			}
 		default:
+			if format == "" {
+				format = "%d"
+			}
 			return func(s Statistics) string {
 				return fmt.Sprintf(format, s.Total)
 			}
@@ -150,20 +162,26 @@
 //	format="%f"    output: "12.000000MiB"
 //	format="% f"   output: "12.000000 MiB"
 func Current(unit interface{}, format string, wcc ...WC) Decorator {
-	if format == "" {
-		format = "% d"
-	}
-	producer := func() DecorFunc {
-		switch unit.(type) {
-		case SizeB1024:
+	producer := func() DecorFunc {
+		switch unit.(type) {
+		case SizeB1024:
+			if format == "" {
+				format = "% d"
+			}
 			return func(s Statistics) string {
 				return fmt.Sprintf(format, SizeB1024(s.Current))
 			}
 		case SizeB1000:
+			if format == "" {
+				format = "% d"
+			}
 			return func(s Statistics) string {
 				return fmt.Sprintf(format, SizeB1000(s.Current))
 			}
 		default:
+			if format == "" {
+				format = "%d"
+			}
 			return func(s Statistics) string {
 				return fmt.Sprintf(format, s.Current)
 			}
@@ -206,20 +224,26 @@
 //	format="%f"    output: "12.000000MiB"
 //	format="% f"   output: "12.000000 MiB"
 func InvertedCurrent(unit interface{}, format string, wcc ...WC) Decorator {
-	if format == "" {
-		format = "% d"
-	}
-	producer := func() DecorFunc {
-		switch unit.(type) {
-		case SizeB1024:
+	producer := func() DecorFunc {
+		switch unit.(type) {
+		case SizeB1024:
+			if format == "" {
+				format = "% d"
+			}
 			return func(s Statistics) string {
 				return fmt.Sprintf(format, SizeB1024(s.Total-s.Current))
 			}
 		case SizeB1000:
+			if format == "" {
+				format = "% d"
+			}
 			return func(s Statistics) string {
 				return fmt.Sprintf(format, SizeB1000(s.Total-s.Current))
 			}
 		default:
+			if format == "" {
+				format = "%d"
+			}
 			return func(s Statistics) string {
 				return fmt.Sprintf(format, s.Total-s.Current)
 			}
diff --git a/decor/speed.go b/decor/speed.go
index 8919cc2..1ebc332 100644
--- a/decor/speed.go
+++ b/decor/speed.go
@@ -67,9 +67,6 @@
 //	unit=SizeB1000(0), format="%.1f"  output: "1.0MB/s"
 //	unit=SizeB1000(0), format="% .1f" output: "1.0 MB/s"
 func MovingAverageSpeed(unit interface{}, format string, average ewma.MovingAverage, wcc ...WC) Decorator {
-	if format == "" {
-		format = "% d"
-	}
 	d := &movingAverageSpeed{
 		WC:       initWC(wcc...),
 		average:  average,
@@ -128,9 +125,6 @@
 //	unit=SizeB1000(0), format="%.1f"  output: "1.0MB/s"
 //	unit=SizeB1000(0), format="% .1f" output: "1.0 MB/s"
 func NewAverageSpeed(unit interface{}, format string, startTime time.Time, wcc ...WC) Decorator {
-	if format == "" {
-		format = "% d"
-	}
 	d := &averageSpeed{
 		WC:        initWC(wcc...),
 		startTime: startTime,
@@ -161,14 +155,23 @@
 func chooseSpeedProducer(unit interface{}, format string) func(float64) string {
 	switch unit.(type) {
 	case SizeB1024:
+		if format == "" {
+			format = "% d"
+		}
 		return func(speed float64) string {
 			return fmt.Sprintf(format, FmtAsSpeed(SizeB1024(math.Round(speed))))
 		}
 	case SizeB1000:
+		if format == "" {
+			format = "% d"
+		}
 		return func(speed float64) string {
 			return fmt.Sprintf(format, FmtAsSpeed(SizeB1000(math.Round(speed))))
 		}
 	default:
+		if format == "" {
+			format = "%f"
+		}
 		return func(speed float64) string {
 			return fmt.Sprintf(format, speed)
 		}