As per ICAO, Annex-14: Accelerate-stop Distance Available (ASDA) is "The length of the take-off run available (TORA) plus the length of the stopway, if provided". Which means that
ASDA = TORA + Stopway (If provided).
Hence, It is very clear that in any case the ASDA can not be less that the TORA of the associated RWY.
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Om Jee Prasad