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diff --git a/packages/merchant-backoffice-ui/src/utils/amount.ts b/packages/merchant-backoffice-ui/src/utils/amount.ts
new file mode 100644
index 000000000..61e33129c
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+++ b/packages/merchant-backoffice-ui/src/utils/amount.ts
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+/*
+ This file is part of GNU Taler
+ (C) 2021 Taler Systems S.A.
+
+ GNU Taler is free software; you can redistribute it and/or modify it under the
+ terms of the GNU General Public License as published by the Free Software
+ Foundation; either version 3, or (at your option) any later version.
+
+ GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along with
+ GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+import { amountFractionalBase, AmountJson, Amounts } from "@gnu-taler/taler-util";
+import { MerchantBackend } from "../declaration";
+
+/**
+ * sums two prices, 
+ * @param one 
+ * @param two 
+ * @returns 
+ */
+const sumPrices = (one: string, two: string) => {
+  const [currency, valueOne] = one.split(':')
+  const [, valueTwo] = two.split(':')
+  return `${currency}:${parseInt(valueOne, 10) + parseInt(valueTwo, 10)}`
+}
+
+/**
+ * merge refund with the same description and a difference less than one minute
+ * @param prev list of refunds that will hold the merged refunds 
+ * @param cur new refund to add to the list
+ * @returns list with the new refund, may be merged with the last
+ */
+export function mergeRefunds(prev: MerchantBackend.Orders.RefundDetails[], cur: MerchantBackend.Orders.RefundDetails) {
+  let tail;
+
+  if (prev.length === 0 ||  //empty list
+    cur.timestamp.t_s === 'never' || //current doesnt have timestamp
+    (tail = prev[prev.length - 1]).timestamp.t_s === 'never' || // last doesnt have timestamp
+    cur.reason !== tail.reason || //different reason
+    cur.pending !== tail.pending || //different pending state
+    Math.abs(cur.timestamp.t_s - tail.timestamp.t_s) > 1000 * 60) {//more than 1 minute difference
+
+    prev.push(cur)
+    return prev
+  }
+
+  prev[prev.length - 1] = {
+    ...tail,
+    amount: sumPrices(tail.amount, cur.amount)
+  }
+
+  return prev
+}
+
+export const rate = (one: string, two: string) => {
+  const a = Amounts.parseOrThrow(one)
+  const b = Amounts.parseOrThrow(two)
+  const af = toFloat(a)
+  const bf = toFloat(b)
+  if (bf === 0) return 0
+  return af / bf
+}
+
+function toFloat(amount: AmountJson) {
+  return amount.value + (amount.fraction / amountFractionalBase);
+}