diff --git a/src/components/KPI/PercentageDifference.js b/src/components/KPI/PercentageDifference.js
new file mode 100644
index 0000000..cdf0c21
--- /dev/null
+++ b/src/components/KPI/PercentageDifference.js
@@ -0,0 +1,44 @@
+export default function calculatePercentageDifference(currentValue, previousValue) {
+    if (!previousValue || previousValue === 0) {
+      return 0;
+    }
+    const difference = currentValue - previousValue;
+    const percentageDifference = (difference / previousValue) * 100;
+    return percentageDifference;
+  }
+  
+  export function calculateTransactionKPI(transactions, periodStart, periodEnd) {
+    const currentTransactions = transactions.filter(tx => {
+      const txDate = new Date(tx.dateTime);
+      return txDate >= periodStart && txDate <= periodEnd;
+    });
+  
+    return currentTransactions.length;
+  }
+
+  export function calculateAgentKPI(agents, periodStart, periodEnd) {
+    const currentAgentActions = agents.filter(agent => {
+      const actionDate = new Date(agent.actionDate);
+      return actionDate >= periodStart && actionDate <= periodEnd;
+    });
+  
+    return currentAgentActions.length;
+  }
+
+  export function calculateCustomerKPI(customers, periodStart, periodEnd) {
+    const currentCustomerInteractions = customers.filter(customer => {
+      const interactionDate = new Date(customer.interactionDate);
+      return interactionDate >= periodStart && interactionDate <= periodEnd;
+    });
+  
+    return currentCustomerInteractions.length;
+  }
+
+  export function calculateDisputeKPI(disputes, periodStart, periodEnd) {
+    const currentDisputes = disputes.filter(dispute => {
+      const disputeDate = new Date(dispute.dateRaised);
+      return disputeDate >= periodStart && disputeDate <= periodEnd;
+    });
+  
+    return currentDisputes.length;
+  }
\ No newline at end of file
diff --git a/src/components/KPI/calculatePercentageChange.js b/src/components/KPI/calculatePercentageChange.js
new file mode 100644
index 0000000..c185dd7
--- /dev/null
+++ b/src/components/KPI/calculatePercentageChange.js
@@ -0,0 +1,52 @@
+import { getCurrentMonthRange } from "./timeRangeHelpers";
+
+export default function calculatePercentageChange(
+  dataArray,
+  dateAccessorFn,
+  optionalFilterFn,
+  getCurrentRangeFn = getCurrentMonthRange,
+  mode = "length", 
+  accessorFn = null 
+) {
+  const { currentRangeStart, currentRangeEnd, previousRangeStart, previousRangeEnd } = getCurrentRangeFn();
+
+  const filterData = (items, start, end) =>
+      items.filter(item => {
+          const date = new Date(dateAccessorFn(item));
+          return date >= start && date <= end && (!optionalFilterFn || optionalFilterFn(item));
+      });
+
+  const currentItems = filterData(dataArray, currentRangeStart, currentRangeEnd);
+  const previousItems = filterData(dataArray, previousRangeStart, previousRangeEnd);
+
+  let currentValue, previousValue, totalValue;
+
+  if (mode === "sum" && accessorFn) {
+      currentValue = currentItems.reduce((acc, item) => acc + accessorFn(item), 0);
+      previousValue = previousItems.reduce((acc, item) => acc + accessorFn(item), 0);
+      totalValue = dataArray.reduce((acc, item) => acc + accessorFn(item), 0);
+  } else {
+      currentValue = currentItems.length;
+      previousValue = previousItems.length;
+      totalValue = dataArray.length;
+  }
+
+  return previousValue === 0
+      ? (currentValue === 0 ? 0 : Math.round((currentValue / totalValue) * 100))  
+      : Math.round(((currentValue - previousValue) / previousValue) * 100);
+}
+
+// Function to calculate percentage of filtered data over total dataset
+export function calculateFilteredPercentage(dataArray, filterFn, mode = "length", accessorFn = null) {
+  let totalValue, filteredValue;
+
+  if (mode === "sum" && accessorFn) {
+      totalValue = dataArray.reduce((acc, item) => acc + accessorFn(item), 0);
+      filteredValue = dataArray.filter(filterFn).reduce((acc, item) => acc + accessorFn(item), 0);
+  } else {
+      totalValue = dataArray.length;
+      filteredValue = dataArray.filter(filterFn).length;
+  }
+
+  return totalValue === 0 ? 0 : Math.round((filteredValue / totalValue) * 100);
+}
diff --git a/src/components/KPI/timeRangeHelpers.js b/src/components/KPI/timeRangeHelpers.js
new file mode 100644
index 0000000..2323065
--- /dev/null
+++ b/src/components/KPI/timeRangeHelpers.js
@@ -0,0 +1,53 @@
+export function getCurrentMonthRange() {
+    const now = new Date();
+    const currentRangeStart = new Date(now.getFullYear(), now.getMonth(), 1);
+    const currentRangeEnd = new Date(now.getFullYear(), now.getMonth() + 1, 0);
+  
+    const previousRangeStart = new Date(now.getFullYear(), now.getMonth() - 1, 1);
+    const previousRangeEnd = new Date(now.getFullYear(), now.getMonth(), 0);
+  
+    return { currentRangeStart, currentRangeEnd, previousRangeStart, previousRangeEnd };
+  }
+  
+  export function getCurrentWeekRange() {
+    const now = new Date();
+    const dayOfWeek = now.getDay(); // 0 (Sun) - 6 (Sat)
+  
+    const currentRangeStart = new Date(now);
+    currentRangeStart.setDate(now.getDate() - dayOfWeek);
+  
+    const currentRangeEnd = new Date(currentRangeStart);
+    currentRangeEnd.setDate(currentRangeStart.getDate() + 6);
+  
+    const previousRangeStart = new Date(currentRangeStart);
+    previousRangeStart.setDate(currentRangeStart.getDate() - 7);
+  
+    const previousRangeEnd = new Date(previousRangeStart);
+    previousRangeEnd.setDate(previousRangeStart.getDate() + 6);
+  
+    return { currentRangeStart, currentRangeEnd, previousRangeStart, previousRangeEnd };
+  }
+  
+  export function getCurrentDayRange() {
+    const now = new Date();
+    const currentRangeStart = new Date(now.setHours(0, 0, 0, 0));
+    const currentRangeEnd = new Date(now.setHours(23, 59, 59, 999));
+  
+    const previousRangeStart = new Date(currentRangeStart);
+    previousRangeStart.setDate(currentRangeStart.getDate() - 1);
+    const previousRangeEnd = new Date(previousRangeStart);
+    previousRangeEnd.setHours(23, 59, 59, 999);
+  
+    return { currentRangeStart, currentRangeEnd, previousRangeStart, previousRangeEnd };
+  }
+  
+  export function getCurrentYearRange() {
+    const now = new Date();
+    const currentRangeStart = new Date(now.getFullYear(), 0, 1);
+    const currentRangeEnd = new Date(now.getFullYear(), 11, 31);
+  
+    const previousRangeStart = new Date(now.getFullYear() - 1, 0, 1);
+    const previousRangeEnd = new Date(now.getFullYear() - 1, 11, 31);
+  
+    return { currentRangeStart, currentRangeEnd, previousRangeStart, previousRangeEnd };
+  }
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