Does anyone have an idea of how to create such chart, i.e with proper smoothing between points with ggplot ? (Theme is not part of the question)
Already found some interesting proposals but nothing that allows important variations between 3 points: For a low value in between two high ones, a clear inflexion is visible resulting in peaks.
I guess a smooth extrapolation between points (polynomial fit ?) would do the trick but did not managed to force passage by exact given values while doing this...
Any help would be appreciated.