Timeboxing for Scrum Events

How long should you allow for Scrum event meetings?

EventGuide4 Week Sprint3 Week Sprint2 Week Sprint1 Week Sprint
Sprint Planning2 hours per week in the sprint8 hours6 hours4 hours2 hours
Daily Scrum (Stand-Up)15 minutes regardless of sprint length15 minutes15 minutes15 minutes15 minutes
Sprint Review1 hour per week in the sprint4 hours3 hours2 hours1 hour
Sprint Retrospective45 minutes per week in the sprint3 hours2.25 hours1.5 hours45 minutes
Scrum Event Timeboxing