Figure 1. The historical distribution of total runoff (as
an areal average depth) accumulated over March, April
and May for the Feather River basin for the period 1955-
2005. Each years value is shown as a point, and the sample
is fitted with Gamma and Log Normal (LN2) distributions.
The values can be expressed either as percentiles,
and the unit standard normal deviates associated with
these percentiles represent the SRI.