Hello @ballardw,
The 'A0'x is an unbreakable space. This is similar to a space in that it doesn't show anything (it's a blank space), but SAS considers it a character. In situations where a regular space would be ignored by SAS procedures an unbreakable space will be treated like any other character ('A', 'W', anything). In this case, when the label is set to be a blank (e.g. label=' ') I believe SAS ignores it and prints the x variable's label. But with an unbreakable space it leaves it alone so you can add a blank label and still allocate the graph space for it.
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