diff -r adccf76bd9bb -r 34ceed6455fa DataSetBuilder.st
--- a/DataSetBuilder.st	Mon Feb 02 20:18:09 1998 +0100
+++ b/DataSetBuilder.st	Mon Feb 02 20:19:04 1998 +0100
@@ -2039,7 +2039,7 @@
     |label list|
 
     list := self seqList.
-    label := 'Column ', list size printString.
+    label := 'Column ', (list size + 1) printString.
     columns add:(DataSetColumnSpec label:label selector:nil) afterIndex:selectedColumnIndex.
     self seqList add:label afterIndex:selectedColumnIndex.
     hasChanged := true.