Another difference between NL and SL corpora is due to the fact that speech data are time functions in a sense in which text data are not. Whilst a writer may consume any time he wants (or needs) to invest in producing a text, a speaker must code and transmit the phonetic information through syllabically and rhythmically organised sound transitions. Speech must run in its own natural time with a typical syllable rate of a value between 120/min and 180/min. The time for writing new text is normally much longer than it takes to read it aloud (which does not mean that silent reading and short-hand-writing cannot be much faster than speaking the text).