Sheet

---
kind: sheet
title: 客户留存模型
columns:
  - {key: customer, label: 客户, type: string}
  - {key: retention, label: 本期留存, type: string}
  - {key: trend, label: 趋势, type: string}
charts:
  - {id: c1, type: bar, title: 客户留存对比, xKey: customer, yKeys: [retention]}
---

```csv
customer,retention,trend
Acme,58%,降
Globex,81%,升
Initech,42%,深降
```

**变化点** → 2 个客户进入风险区。

columns:
  - {key: revenue, label: 收入, type: number}
  - {key: cost, label: 成本, type: number}
  - {key: margin, label: 毛利率, type: formula, expr: "(revenue - cost) / revenue"}