Indicate on the LCA page when an event is partially or fully outside the analysis period.

[xtitter]

Right now, if the "included for analysis" events are all outside the analysis period -- i.e., they start after the analysis period end date -- they analyze page happily runs and doesn't actually process any events.

It might also be useful to add a checkbox for "Analyze full duration of all events" which needs to be unchecked to set the years field.