diff --git a/system/reporting/frame_builder.go b/system/reporting/frame_builder.go
index 3c7ec5162..7fec50979 100644
--- a/system/reporting/frame_builder.go
+++ b/system/reporting/frame_builder.go
@@ -111,7 +111,7 @@ func (b *reportFrameBuilder) freshFrame() {
 	if b.frame != nil {
 		aux := *b.frame
 		b.frame = &aux
-		b.frame.Rows = nil
+		b.frame.Rows = []FrameRow{}
 		return
 	}
 
@@ -120,6 +120,8 @@ func (b *reportFrameBuilder) freshFrame() {
 		Source: b.def.Source,
 		Ref:    b.def.Ref,
 
+		Rows: []FrameRow{},
+
 		Columns: b.def.Columns,
 		Sort:    b.def.Sort,
 		Filter:  b.def.Filter,