J_T
On the thread Brian referred to, a poster offered a LH "formula" that for every knot over V1 that the reject is initiated, the plane will overrun at 10 knots. That is, a 1 knot exceedence of V1 will result in a 10 knot overrun on a limiting runway. A mad scientist ran the numbers and thought that was correct in the 6-9 knot range, a greater multiple at slower speeds and a lower one at greater speeds. Works for me.
GF