The probability that a particular loss will occur once in a century is 1% (one year in 100 years). The z-value of that is given in the table as -2.326, so the corresponding x-value is ...
x = µ +zσ = 14.2 -2.326·12.85 = -15.69
We expect an annual loss of at least 15.7% once in a century.
