Give option to use various types of trend lines as well as set intercepts.

[Anonymous]

Currently, the only trend line option is an on/off switch that gives a linear trend line. 

It would be helpful to give the user the option to create logarithmic, expotential, polynomial trend lines, as well as give the ability to set a y intercept. Would be nice to give R squared values as well.

[TickboxPhil]

Yes, it's embarrassing we can't add standard trends (exp/log/poly), only linear (and that should have an intercept option), to allow comparison.

Spotfire and others can (Excel does it nicely!), so they win out massively when illustrating trajectories etc. Seems clunky and unflexible to have to resort to an R chart just for this.