Figure 12 shows that as long as the number of buckets per day is not extremely large, and the sample length is not extremely small, the probability that VPIN was in the upper quartile one volume bucket prior to a 0.75% or greater absolute return will be between 80% and 90%. This result not only means that VPIN anticipates a large proportion of extreme volatility events, but also that toxicity-induced volatility seems to be a significant source of overall volatility.