As a user of the API, I'd like to be able to define conditional rolling rule evaluations, which are used in certain work regulations.

An example of such a rule is: If 16 or more night shifts are worked in a 16-week period, then the employee must work an average of 40 hours per week.

Such an expression consists of:

Condition: If 16 or more night shifts are worked in a 16-week period

Consequence: The employee must work an average of 40 hours per week

This is an extension of the existing rolling window API.