Plot axis should be event occurrences

[motib]

The plot assumes that the values should be plotted against time. However, it makes sense to plot against event occurrences in general and not just time. Time can be computed from occurrences / frequency. Alternatively, events and time could be two separate options.

[riedo]

I think it is interesting to keep the time notion for events that are not synchronous; having the choice plotting against time or event occurences would be nice.

[stephanemagnenat]

Ideally, there should be an option to choose between the two, but we do not have the work force now.