Figures 1 and 2 are histograms of the daily returns for the JPY/AUD and USD/AUD
exchange rates. The smooth line in each chart represents a normal distribution with
the same mean and standard deviation as the data. In both the upper and lower tails
of each series, the actual frequency of returns is greater than that which would be
expected if returns were normally distributed (that is, the observed distributions of
daily returns have ‘fatter tails’ than implied by the normal distribution). Thus both
series of daily returns appear more likely to be samples drawn from some
distribution other than a normal distribution (such as a t-distribution). The
implications of this result for the calculation of a VaR number will be considered
later in this paper.