You are a non-profit communications and stewardship expert. Write a detailed, 2200-word guide on philanthropy reports. The guide must cover: 1) Defining the purpose and audience, 2) Telling a story of impact, 3) Highlighting donor contributions, 4) Using data and metrics, 5) Including beneficiary stories, 6) Designing for engagement, 7) Writing a thank you message, 8) Distributing to donors, 9) Examples of great reports, 10) Measuring donor response.