diff --git a/app/lib/yearMonthActions.ts b/app/lib/yearMonthActions.ts
new file mode 100644
index 0000000..335012d
--- /dev/null
+++ b/app/lib/yearMonthActions.ts
@@ -0,0 +1,103 @@
+'use server';
+
+import { revalidatePath } from 'next/cache';
+import { redirect } from 'next/navigation';
+import clientPromise from './mongodb';
+import { ObjectId } from 'mongodb';
+import { BillingLocation } from './db-types';
+
+/**
+ * Server-side action which adds a new month to the database
+ * @param locationId location of the bill
+ * @param billId ID of the bill
+ * @param prevState previous state of the form
+ * @param formData form data
+ * @returns 
+ */
+export async function addYearMonth(yearMonthString: string) {
+
+    // update the bill in the mongodb
+    const client = await clientPromise;
+    const db = client.db("rezije");
+    const yearMonth = parseInt(yearMonthString);
+
+    const prevYearMonth = (yearMonth - 1) % 100  === 0 ? yearMonth - 89 : yearMonth - 1;
+
+    // find all locations for the previous month
+    const prevMonthLocations = await db.collection<BillingLocation>("lokacije").find({ yearMonth: prevYearMonth });
+
+    const newMonthLocationsCursor = prevMonthLocations.map((prevLocation) => {
+        return({
+            // copy all the properties from the previous location
+            ...prevLocation,
+            // assign a new ID
+            _id: (new ObjectId()).toHexString(),
+            yearMonth,
+            // copy bill array, but set all bills to unpaid and remove attachments and notes
+            bills: prevLocation.bills.map((bill) => {
+                return {
+                    ...bill,
+                    paid: false,
+                    attachment: null,
+                    notes: null,
+                }
+            })
+        } as BillingLocation);
+    });
+
+    const newMonthLocations = await newMonthLocationsCursor.toArray()
+    await db.collection<BillingLocation>("lokacije").insertMany(newMonthLocations);
+
+    // clear the cache for the path
+    revalidatePath('/');
+    // go to the bill list
+    redirect('/');
+}
+
+export async function gotoHome() {
+    redirect('/');   
+}
+
+export const fetchBillById = async (locationID:string, billID:string) => {
+    const client = await clientPromise;
+    const db = client.db("rezije");
+
+    // find a location with the given locationID
+    const billLocation = await db.collection<BillingLocation>("lokacije").findOne({ _id: locationID })
+
+    if(!billLocation) {
+        console.log(`Location ${locationID} not found`);
+        return(null);
+    }
+
+    // find a bill with the given billID
+    const bill = billLocation?.bills.find(({ _id }) => _id.toString() === billID);
+
+    if(!bill) {
+        console.log('Bill not found');
+        return(null);
+    }
+
+    return(bill);
+}
+
+export const deleteBillById = async (locationID:string, billID:string) => {
+    const client = await clientPromise;
+    const db = client.db("rezije");
+
+    // find a location with the given locationID
+    const post = await db.collection<BillingLocation>("lokacije").updateOne(
+        {
+            _id: locationID // find a location with the given locationID
+        },
+        {
+            // remove the bill with the given billID
+            $pull: {
+                bills: {
+                    _id: billID
+                }
+            }
+        });
+    
+    return(post.modifiedCount);
+}
\ No newline at end of file
diff --git a/app/page.tsx b/app/page.tsx
index dad454b..83f5481 100644
--- a/app/page.tsx
+++ b/app/page.tsx
@@ -3,14 +3,18 @@ import { MonthTitle } from './ui/MonthTitle';
 import { AddMonthButton } from './ui/AddMonthButton';
 import { AddLocationButton } from './ui/AddLocationButton';
 import clientPromise from './lib/mongodb';
-import { Location } from './lib/db-types';
+import { BillingLocation } from './lib/db-types';
+
+const calcNextYearMonth = (yearMonth: number) => {
+  return(yearMonth % 100 === 12 ? yearMonth + 89 : yearMonth + 1);
+}
 
 export const Page = async () => {
 
  const client = await clientPromise;
  const db = client.db("rezije");
 
- const locations = await db.collection<Location>("lokacije")
+ const locations = await db.collection<BillingLocation>("lokacije")
     .find({})
     .sort({ yearMonth: -1 }) // sort by yearMonth descending
     .limit(20)
@@ -18,7 +22,7 @@ export const Page = async () => {
 
  return (
     <main className="flex min-h-screen flex-col p-6 bg-base-300">
-        <AddMonthButton />
+        <AddMonthButton yearMonth={calcNextYearMonth(locations[0].yearMonth)} />
         {
           locations.map((location, ix, array) => {
             
diff --git a/app/ui/AddMonthButton.tsx b/app/ui/AddMonthButton.tsx
index 8a14523..cee605f 100644
--- a/app/ui/AddMonthButton.tsx
+++ b/app/ui/AddMonthButton.tsx
@@ -1,9 +1,11 @@
 import { PlusCircleIcon } from "@heroicons/react/24/outline";
+import React from "react";
 
 export interface AddMonthButtonProps {
+    yearMonth: number;
 }
 
-export const AddMonthButton:FC<AddMonthButtonProps> = () =>
-<span className='grid self-center' data-tip="Dodaj novi mjesec">
+export const AddMonthButton:React.FC<AddMonthButtonProps> = ({ yearMonth }) =>
+<a href={`/year-month/${yearMonth}/add`} className='grid self-center tooltip' data-tip="Dodaj novi mjesec">
     <PlusCircleIcon className="h-[1em] w-[1em] cursor-pointer text-4xl" />
-</span>
+</a>
diff --git a/app/year-month/[id]/add/page.tsx b/app/year-month/[id]/add/page.tsx
new file mode 100644
index 0000000..b5a43ec
--- /dev/null
+++ b/app/year-month/[id]/add/page.tsx
@@ -0,0 +1,11 @@
+import { addYearMonth } from '@/app/lib/yearMonthActions';
+import { revalidatePath } from 'next/cache';
+import { redirect } from 'next/navigation';
+
+export default async function Page({ params:{ id } }: { params: { id:string } }) {
+
+    await addYearMonth(id);
+
+    revalidatePath('/');
+    redirect(`/`);
+}
\ No newline at end of file