diff --git a/src/components/05_quotation/ProductItem.vue b/src/components/05_quotation/ProductItem.vue
index e5b3a452..9c585d3f 100644
--- a/src/components/05_quotation/ProductItem.vue
+++ b/src/components/05_quotation/ProductItem.vue
@@ -1,10 +1,10 @@
 <script lang="ts" setup>
+import { computed } from 'vue';
+import { precisionRound } from 'src/utils/arithmetic';
+
 import { QTableProps } from 'quasar';
 import TableComponents from 'src/components/TableComponents.vue';
 import { QuotationPayload } from 'src/stores/quotations/types';
-import { computed } from 'vue';
-
-const calTax = defineModel('calTax', { default: false });
 
 defineEmits<{
   (e: 'delete', index: number): void;
@@ -14,26 +14,25 @@ const rows = defineModel<
   Required<QuotationPayload['productServiceList'][number]>[]
 >('rows', { required: true });
 
-function calcPrice(data: (typeof rows.value)[number]) {
-  const price = data.pricePerUnit * data.amount;
-  const discount = Math.round(price * data.discount) / 100;
-  const vat = Math.round((price - discount) * data.vat) / 100;
+function calcPrice(c: (typeof rows.value)[number]) {
+  const price = precisionRound(c.pricePerUnit * c.amount);
+  const discount = precisionRound(price * (c.discount || 0));
+  const vat = precisionRound((price - discount) * c.vat);
 
-  return (price * 100 - discount * 100 + vat * 100) / 100;
+  return precisionRound(price - discount + vat);
 }
 
 const summary = computed(() =>
   rows.value.reduce(
     (a, c) => {
-      const price = c.pricePerUnit * c.amount;
-      const discount = Math.round(price * c.discount) / 100;
-      const vat = Math.round((price - discount) * c.vat) / 100;
+      const price = precisionRound(c.pricePerUnit * c.amount);
+      const discount = precisionRound(price - (c.discount || 0));
+      const vat = precisionRound((price - discount) * c.vat);
 
-      a.totalPrice = (a.totalPrice * 100 + price * 100) / 100;
-      a.totalDiscount = (a.totalDiscount * 100 + discount * 100) / 100;
-      a.vat = (a.vat * 100 + vat * 100) / 100;
-      a.finalPrice =
-        (a.finalPrice * 100 + price * 100 - discount * 100 + vat * 100) / 100;
+      a.totalPrice = precisionRound(a.totalPrice + price);
+      a.totalDiscount = precisionRound(a.totalDiscount + discount);
+      a.vat = precisionRound(a.vat + vat);
+      a.finalPrice = precisionRound(a.totalPrice - a.totalDiscount + a.vat);
 
       return a;
     },
@@ -172,11 +171,7 @@ const columns = [
             type="number"
             style="width: 70px"
             v-model="props.row.discount"
-          >
-            <template v-slot:append>
-              <span class="text-caption no-padding">%</span>
-            </template>
-          </q-input>
+          />
         </q-td>
       </template>