> For the complete documentation index, see [llms.txt](https://kb.logicerp.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://kb.logicerp.com/logic-erp-learning-hub-tutorials-and-best-practices/setups/configurations/purchase-voucher-configurations/other-settings-1/update-rates-from-formula-before-saving.md).

# Update Rates from formula before saving

**YouTube:** [How to Update Rates from Formula before Saving in Purchase?](https://www.youtube.com/watch?v=RNzyAQtX6mk)

## How to Update Rates from Formula before Saving in Purchase?

\
 In this tutorial, we will discuss an essential feature in purchase entry that allows automated rate calculation using predefined formulas.

**Steps to Configure & Apply the Feature:**

* Navigate to the "**Purchase Voucher Configuration"**.
* Locate the option and enable **"**Update Rates from formula before saving**"**.

<figure><img src="/files/zMuNg1ZPFBxgioeqJJwI" alt=""><figcaption><p>Let's keep this feature enable to observe it's Impact.</p></figcaption></figure>

### Implement in Purchase Voucher:

* Create a new "Purchase Voucher".
* Define the item and its details.
* The purchase rate is automatically calculated using a predefined formula set in the purchase voucher configuration.
* Save the purchase voucher.
  * Note: Currently, we have not defined the scheme amount, so the purchase rate is 1048.95.

<figure><img src="/files/PgFtVCkv8ipAVd8ID5H8" alt=""><figcaption><p>This picture displays the Rate without the Scheme Rs.</p></figcaption></figure>

### **Define Scheme Amount:**

* To define the scheme in rupees, press **Shift + F5** in the rate field.

<figure><img src="/files/BCDsDe9DJIbtirA5jTYl" alt=""><figcaption><p>Define the Scheme Rs here as instructed.</p></figcaption></figure>

### **Purchase Rate After Defining Scheme(Rs)**

* **Modify the Recently Created Purchase Bill**

<figure><img src="/files/eRem7byYvco2sf2H2Dao" alt=""><figcaption><p>In this picture, you can see that the rate has been updated successfully.</p></figcaption></figure>

✔ **Result:** The purchase rate is successfully updated as per the predefined formula.

### **Conclusion**

This feature helps in automating purchase rate calculations, reducing manual errors, and ensuring accurate billing.


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