GROWTH(known_y's[,known_x's,new_x's,const])
GROWTH .
@known_x , {1, 2, 3, ...}. @new_x , @known_x.
GROWTH @new_x.
@known_y @known_x , GROWTH #NUM!.
@const (FALSE), , .. b 0. (TRUE).
LOGEST, GROWTH, TREND.