HP 10bII+ User Manual page 172

Forecasting
VI Appendix B: More About Calculations
Name
Best Fit
Linear
Logarithm
Exponential
Power
Exponent
Inverse
Fit
Automatically selects fit
m*x+b
m*ln(x)+b
(m*x)
b*e
m
b*x
x
b*m
m/x+b