> ## Documentation Index
> Fetch the complete documentation index at: https://docs.flagsync.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Examples
> See how numeric metrics aggregate event values in FlagSync.
## Examples
For a `discount-rate` flag with variants 0%, 20%, and 30%, impressions are logged when users see the applied discount, and events are tracked when they complete a purchase.
```tsx checkout-page.tsx theme={null}
// Step 1: Log impression
const discountRate = client.flag('discount-rate', 0.00);
// Step 2: Track the purchase event
const item = {
productId: '0x123',
price: 50.00,
discount: discountRate // 0.3 (30%)
};
client.track('purchase_event', null, item);
```
### Average or Sum Purchase Price
Let’s explore how an average or sum metric tracks purchase value for the `discount-rate` flag, testing which variant drives higher spending:
Select `purchase_event` and enter `price` as the value field to aggregate:
* [Events](/events/overview) auto-populate from `client.track()`.
* [Property Events](/events/tracking#property-events) let you derive multiple metrics from one `purchase_event`.
Aggregate by average or sum:
See a simulated FlagSync dashboard for the `discount-rate` experiment, testing how discount variants impact average purchase value:
* **Trend**: The chart shows 30% (pink) leading at \$147 average purchase value, followed by 20% (orange) at \$108, with 0% (blue) at \$83.
The 30% variant is the clear winner, increasing average purchase value by 76.4% over the baseline.
## Next Steps
* Learn concepts in [Numeric Metrics: Overview](/metrics-numeric/overview).
* Explore [Experiments](/experiments/overview).