Zend certified PHP/Magento developer

Rounded value Tierprice percentage

I’m trying to set a decimal value to a percentage discount on a tierprice.

The problem is that when it’s saved the value is becoming an int instead of a decimal.

Example
if I set a percentage to 1.23% after save => 1%

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after saving it

enter image description here

Any way that it keeps the decimal value ?

Thanks