CSS3 property values, non-negative percentages

Hi all,

in the definition of <percentage> in CSS3 Values and Units [1], the  
following editor's note (tagged as "issue", actually) is present:

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Do we need a "non-negative percentage", e.g. for "font-size"?
---

There are quite a few <non-negative number> values in CSS3-Speech  
properties, so I would personally welcome a <non-negative percentage>  
value type. This would save a line of redundant prose in each affected  
property description, and it would be more consistent with the "non- 
negative" number and integer approach.

Regards, Daniel