Write a post-event impact report for [EVENT NAME].
Structure:
1. **Executive Summary**: Key headlines
2. **Attendance & Demographics**: Total vs target, breakdown by type
3. **Programme Highlights**: Most popular sessions, standout moments
4. **Engagement Metrics**: Social reach, hashtag impressions, app usage
5. **Financial Summary**: Revenue vs budget, profit/loss
6. **Sponsor Value**: Impressions delivered, leads generated
7. **Testimonials**: 5-8 impactful quotes
8. **Lessons Learned**: What worked, what didn't
9. **Next Steps**: Date for next edition, strategic priorities