This is one version of a z table. It gives the probability that a standard normal random variable, Z, will exceed a given positive value, z. Equivalently, it gives the probability that any normal random variable will exceed its mean by more than a given number of standard deviations. See Z-score for more information. To look up the probability that Z exceeds 1.96, for example, look in the row for 1.9 and the column for 0.06; the probability is 0.0250.