Figure 10 September CET predictions of multiple regression model using September P, S  & C indices for period used to
develop model (1881-1970) and for 1971-2003 compared with observed September CET 1881-2003 and the
model errors (observed - predicted CET).

Equation: Sep CET = 12.907 + (0.00535 x Sep C) + (0.06051 x Sep S) + (-0.01557 x Sep C) which explains 36% of variation in Sep CET.