Figure 5 April CET predictions of multiple regression model using April P, S  & C indices for period used
to develop model (1881-1970) and for 1971-2003 compared with observed April CET 1881-2003 and the
model errors (observed - predicted CET).

Equation: Apr CET = 7.846 + (0.01366 x Apr P) + (0.0566 x Feb S) + (-0.01924 x Apr C) which explains 27% of variation in Apr CET.