diff --git a/app/lib/actions/locationActions.ts b/app/lib/actions/locationActions.ts
index a06c6b2..dc7192b 100644
--- a/app/lib/actions/locationActions.ts
+++ b/app/lib/actions/locationActions.ts
@@ -33,7 +33,7 @@ const UpdateLocation = FormSchema.omit({ _id: true });
  * @param formData form data
  * @returns 
  */
-export const updateOrAddLocation = withUser(async (user:AuthenticatedUser, locationId?: string, yearMonth?: string, prevState:State, formData: FormData) => {
+export const updateOrAddLocation = withUser(async (user:AuthenticatedUser, locationId?: string, year?: string, month?: string, prevState:State, formData: FormData) => {
 
     const validatedFields = UpdateLocation.safeParse({
         locationName: formData.get('locationName'),
@@ -70,14 +70,15 @@ export const updateOrAddLocation = withUser(async (user:AuthenticatedUser, locat
                     notes: locationNotes,
                 }
             });
-    } else if(yearMonth) {
+    } else if(year && month) {
         await dbClient.collection<BillingLocation>("lokacije").insertOne({
             _id: (new ObjectId()).toHexString(),
             userId,
             userEmail,
             name: locationName,
             notes: locationNotes,
-            yearMonth: parseInt(yearMonth), // ToDo: get the current year and month
+            year: parseInt(year), // ToDo: get the current year and month
+            month: parseInt(month), // ToDo: get the current year and month
             bills: [],
         });
     }
@@ -98,7 +99,7 @@ export const fetchAllLocations = withUser(async (user:AuthenticatedUser, pageIx:
     // fetch `pageSize` locations for the given page index
     const locations = await dbClient.collection<BillingLocation>("lokacije")
         .find({ userId })
-        .sort({ yearMonth: -1, name: 1 })
+        .sort({ year: -1, month: -1, name: 1 })
         .skip(pageIx * pageSize)
         .limit(pageSize)
         .toArray();
diff --git a/app/lib/actions/yearMonthActions.ts b/app/lib/actions/monthActions.ts
similarity index 53%
rename from app/lib/actions/yearMonthActions.ts
rename to app/lib/actions/monthActions.ts
index 21cc856..7689d62 100644
--- a/app/lib/actions/yearMonthActions.ts
+++ b/app/lib/actions/monthActions.ts
@@ -16,20 +16,23 @@ import { withUser } from '../auth';
  * @param formData form data
  * @returns 
  */
-export const addYearMonth = withUser(async (user:AuthenticatedUser, yearMonthString: string) => {
+export const addMonth = withUser(async (user:AuthenticatedUser, yearString: string, monthString: string) => {
     const { id: userId } = user;
 
     // update the bill in the mongodb
     const dbClient = await getDbClient();
 
-    const yearMonth = parseInt(yearMonthString);
+    const year = parseInt(yearString);
+    const month = parseInt(monthString);
 
-    const prevYearMonth = (yearMonth - 1) % 100  === 0 ? yearMonth - 89 : yearMonth - 1;
+    const prevYear = month === 1 ? year - 1 : year;
+    const prevMonth = month === 1 ? 12 : month - 1;
 
     // find all locations for the previous month
     const prevMonthLocations = await dbClient.collection<BillingLocation>("lokacije").find({
         userId, // make sure that the locations belongs to the user
-        yearMonth: prevYearMonth
+        year: prevYear,
+        month: prevMonth,
     });
 
     const newMonthLocationsCursor = prevMonthLocations.map((prevLocation) => {
@@ -38,7 +41,8 @@ export const addYearMonth = withUser(async (user:AuthenticatedUser, yearMonthStr
             ...prevLocation,
             // assign a new ID
             _id: (new ObjectId()).toHexString(),
-            yearMonth,
+            year: year,
+            month: month,
             // copy bill array, but set all bills to unpaid and remove attachments and notes
             bills: prevLocation.bills.map((bill) => {
                 return {
@@ -64,52 +68,13 @@ export async function gotoHome() {
     redirect('/');   
 }
 
-export const fetchBillById = withUser(async (user:AuthenticatedUser, locationID:string, billID:string) => {
+export const fetchAvailableYears = withUser(async (user:AuthenticatedUser) => {
     const { id: userId } = user;
 
     const dbClient = await getDbClient();
 
-    // find a location with the given locationID
-    const billLocation = await dbClient.collection<BillingLocation>("lokacije").findOne({
-        _id: locationID,
-        userId // make sure that the location belongs to the user
-     })
+    // query mnogodb for all `yearMonth` values
+    const yearMonths = await dbClient.collection<BillingLocation>("lokacije").distinct("year", { userId });
 
-    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);
+    return(yearMonths);
 })
-
-export const deleteBillById = withUser(async (user:AuthenticatedUser, locationID:string, billID:string) => {
-    const { id: userId } = user;
-
-    const dbClient = await getDbClient();
-
-    // find a location with the given locationID
-    const post = await dbClient.collection<BillingLocation>("lokacije").updateOne(
-        {
-            _id: locationID, // find a location with the given locationID
-            userId // make sure that the location belongs to the user
-        },
-        {
-            // remove the bill with the given billID
-            $pull: {
-                bills: {
-                    _id: billID
-                }
-            }
-        });
-    
-    return(post.modifiedCount);
-});
\ No newline at end of file
diff --git a/app/lib/db-types.ts b/app/lib/db-types.ts
index fe4087d..d7bdc20 100644
--- a/app/lib/db-types.ts
+++ b/app/lib/db-types.ts
@@ -1,4 +1,5 @@
 import { ObjectId } from "mongodb";
+import { inter } from "../ui/fonts";
 
 export interface BillAttachment {
     fileName: string;
@@ -17,8 +18,10 @@ export interface BillingLocation {
     userEmail?: string | null;
     /** name of the location */
     name: string;
-    /** the value is encoded as yyyymm (i.e. 202301) */
-    yearMonth: number;
+    /** billing period year */
+    year: number;
+    /** billing period month */
+    month: number;
     /** array of bills */
     bills: Bill[];
     /** (optional) notes */
diff --git a/app/lib/format.ts b/app/lib/format.ts
index 4be1d36..cd0ea6a 100644
--- a/app/lib/format.ts
+++ b/app/lib/format.ts
@@ -1,6 +1,4 @@
 
-export const formatYearMonth = (yearMonth: number): string => {
-  const year = Math.floor(yearMonth / 100);
-  const month = yearMonth % 100;
+export const formatYearMonth = (year: number, month:number): string => {
   return `${year}-${month<10?"0":""}${month}`;
 }
diff --git a/app/location/[id]/add/page.tsx b/app/location/[id]/add/page.tsx
index 7b7be22..26036aa 100644
--- a/app/location/[id]/add/page.tsx
+++ b/app/location/[id]/add/page.tsx
@@ -1,6 +1,7 @@
 import { LocationEditForm } from '@/app/ui/LocationEditForm';
 
-export default async function Page({ params:{ id:yearMonth } }: { params: { id:string } }) {
+export default async function Page({ params:{ id } }: { params: { id:string } }) {
 
-    return (<LocationEditForm yearMonth={yearMonth} />);
+    const [year, month] = id.split("-");
+    return (<LocationEditForm year={year} month={month} />);
 }
\ No newline at end of file
diff --git a/app/page.tsx b/app/page.tsx
index 3271209..91f5f7e 100644
--- a/app/page.tsx
+++ b/app/page.tsx
@@ -6,14 +6,19 @@ import { PageFooter } from './ui/PageFooter';
 import { isAuthErrorMessage } from '@/app/lib/auth';
 import { fetchAllLocations } from './lib/actions/locationActions';
 import { formatCurrency } from './lib/formatStrings';
+import { fetchAvailableYears } from './lib/actions/monthActions';
 
-const getNextYearMonth = (yearMonth:number) => {
-  return(yearMonth % 100 === 12 ? yearMonth + 89 : yearMonth + 1);
+const getNextYearMonth = (year:number, month:number) => {
+  return({
+    year: month<12 ? year+1 : year,
+    month: month<12 ? month+1 : 1
+  });
 }
 
 export const Page = async () => {
 
  const locations = await fetchAllLocations();
+ const availableYearMonths = await fetchAvailableYears();
 
  if(isAuthErrorMessage(locations)) {
   return (
@@ -24,11 +29,14 @@ export const Page = async () => {
 
   // if the database is in it's initial state, show the add location button for the current month
   if(locations.length === 0) {
-    const currentYearMonth = new Date().getFullYear() * 100 + new Date().getMonth() + 1;
+    
+    const currentYear = new Date().getFullYear();
+    const currentMonth = new Date().getMonth() + 1; 
+    
     return (
       <main className="flex min-h-screen flex-col p-6 bg-base-300">
-        <MonthTitle yearMonth={currentYearMonth} />
-        <AddLocationButton yyyymm={currentYearMonth} />
+        <MonthTitle year={currentYear} month={currentMonth} />
+        <AddLocationButton year={currentYear} month={currentMonth} />
         <PageFooter />
       </main>
     );
@@ -38,13 +46,13 @@ export const Page = async () => {
 
  return (
     <main className="flex min-h-screen flex-col p-6 bg-base-300">
-        <AddMonthButton nextYearMonth={getNextYearMonth(locations[0].yearMonth)} />
+        <AddMonthButton {...getNextYearMonth(locations[0].year, locations[0].month)} />
         {
           locations.map((location, ix, array) => {
 
-            const isFirstLocationInMonth = ix === 0 || location.yearMonth !== array[ix-1].yearMonth;
-            const isLastLocationInMonth = location.yearMonth !== array[ix+1]?.yearMonth;
-            const isLastLocationOfFirstMonth = isLastLocationInMonth && location.yearMonth === array[0].yearMonth;
+            const isFirstLocationInMonth = ix === 0 || location.year !== array[ix-1].year || location.month !== array[ix-1].month;
+            const isLastLocationInMonth = location.year !== array[ix+1]?.year || location.month !== array[ix+1]?.month;
+            const isLastLocationOfFirstMonth = isLastLocationInMonth && location.year === array[0].year && location.month === array[0].month;
 
             if(isFirstLocationInMonth) {
               monthlyExpense = 0;
@@ -57,13 +65,13 @@ export const Page = async () => {
                 {
                   // show month title above the first LocationCard in the month
                   isFirstLocationInMonth ?
-                    <MonthTitle key={location.yearMonth} yearMonth={location.yearMonth} /> : null
+                    <MonthTitle key={`${location.year}-${location.month}`} year={location.year} month={location.month} /> : null
                 }
                 <LocationCard key={`${location._id}`} location={location} />
                 {
                   // show AddLocationButton as a last item in the firts month
                   isLastLocationOfFirstMonth ?
-                    <AddLocationButton key={`add-loc-${location.yearMonth}`} yyyymm={location.yearMonth} /> : null
+                    <AddLocationButton key={`add-loc-${location.year}-${location.month}`} year={location.year} month={location.month} /> : null
                 }
                 {
                   isLastLocationInMonth && monthlyExpense>0 ?
@@ -80,6 +88,7 @@ export const Page = async () => {
           })
         }
         <PageFooter />
+        { availableYearMonths.map(ym => <p key={`year-month-${ym}`}>{ym}</p>) }
     </main>
   );
 }
diff --git a/app/ui/AddLocationButton.tsx b/app/ui/AddLocationButton.tsx
index fbf0737..7191385 100644
--- a/app/ui/AddLocationButton.tsx
+++ b/app/ui/AddLocationButton.tsx
@@ -2,13 +2,15 @@ import { PlusCircleIcon } from "@heroicons/react/24/outline";
 
 
 export interface AddLocationButtonProps {
-    /** year month at which the new billing location should be addes */
-    yyyymm: number
+    /** year at which the new billing location should be addes */
+    year: number
+    /** month at which the new billing location should be addes */
+    month: number
 }
 
-export const AddLocationButton:React.FC<AddLocationButtonProps> = ({yyyymm}) =>
+export const AddLocationButton:React.FC<AddLocationButtonProps> = ({year,month}) =>
 <div className="card card-compact card-bordered max-w-[36em] bg-base-100 shadow-s my-1">
-    <a href={`/location/${yyyymm}/add`} className="card-body tooltip self-center" data-tip="Add a new billing location">
+    <a href={`/location/${year}-${month<10?"0":""}${month}/add`} className="card-body tooltip self-center" data-tip="Add a new billing location">
         <span className='grid self-center' data-tip="Add a new billing location">
             <PlusCircleIcon className="h-[1em] w-[1em] cursor-pointer text-4xl" />
         </span>
diff --git a/app/ui/AddMonthButton.tsx b/app/ui/AddMonthButton.tsx
index dc62ed8..535b9bc 100644
--- a/app/ui/AddMonthButton.tsx
+++ b/app/ui/AddMonthButton.tsx
@@ -2,10 +2,11 @@ import { PlusCircleIcon } from "@heroicons/react/24/outline";
 import React from "react";
 
 export interface AddMonthButtonProps {
-    nextYearMonth: number;
+    year: number;
+    month: number;
 }
 
-export const AddMonthButton:React.FC<AddMonthButtonProps> = ({ nextYearMonth }) =>
-<a href={`/year-month/${nextYearMonth}/add`} className='grid self-center tooltip' data-tip="Dodaj novi mjesec">
+export const AddMonthButton:React.FC<AddMonthButtonProps> = ({ year, month }) =>
+<a href={`/year-month/${year}-${month<10?"0":""}${month}/add`} className='grid self-center tooltip' data-tip="Dodaj novi mjesec">
     <PlusCircleIcon className="h-[1em] w-[1em] cursor-pointer text-4xl" />
 </a>
diff --git a/app/ui/LocationCard.tsx b/app/ui/LocationCard.tsx
index addc8ca..d51eb1f 100644
--- a/app/ui/LocationCard.tsx
+++ b/app/ui/LocationCard.tsx
@@ -11,7 +11,7 @@ export interface LocationCardProps {
     location: BillingLocation
 }
 
-export const LocationCard:FC<LocationCardProps> = ({location: { _id, name, yearMonth, bills }}) => {
+export const LocationCard:FC<LocationCardProps> = ({location: { _id, name, year, month, bills }}) => {
 
     // sum all the billAmounts
     const monthlyExpense = bills.reduce((acc, bill) => acc + (bill.payedAmount ?? 0), 0);
@@ -22,7 +22,7 @@ export const LocationCard:FC<LocationCardProps> = ({location: { _id, name, yearM
                 <a href={`/location/${_id}/edit`} className="card-subtitle tooltip" data-tip="Edit Location">
                     <Cog8ToothIcon className="h-[1em] w-[1em] absolute cursor-pointer top-3 right-3 text-2xl" />
                 </a>
-                <h2 className="card-title">{formatYearMonth(yearMonth)} {name}</h2>
+                <h2 className="card-title">{formatYearMonth(year, month)} {name}</h2>
                 <div className="card-actions">
                     {
                         bills.map(bill => <BillBadge key={`${bill._id}`} locationId={_id} bill={bill} />)
diff --git a/app/ui/LocationEditForm.tsx b/app/ui/LocationEditForm.tsx
index 0cd2a79..64769fa 100644
--- a/app/ui/LocationEditForm.tsx
+++ b/app/ui/LocationEditForm.tsx
@@ -10,14 +10,16 @@ import { gotoHome } from "../lib/actions/billActions";
 export interface LocationEditFormProps {
     /** location which should be edited */
     location?: BillingLocation,
-    /** year month at a new billing location should be assigned */
-    yearMonth?: string
+    /** year at a new billing location should be assigned */
+    year?: string
+    /** month at a new billing location should be assigned */
+    month?: string
 }
 
-export const LocationEditForm:FC<LocationEditFormProps> = ({ location, yearMonth }) =>
+export const LocationEditForm:FC<LocationEditFormProps> = ({ location, year, month }) =>
 {
     const initialState = { message: null, errors: {} };
-    const handleAction = updateOrAddLocation.bind(null, location?._id, yearMonth);
+    const handleAction = updateOrAddLocation.bind(null, location?._id, year, month);
     const [ state, dispatch ] = useFormState(handleAction, initialState);
 
     // redirect to the main page
diff --git a/app/ui/MonthTitle.tsx b/app/ui/MonthTitle.tsx
index babe101..f02940f 100644
--- a/app/ui/MonthTitle.tsx
+++ b/app/ui/MonthTitle.tsx
@@ -2,8 +2,9 @@ import { FC } from "react";
 import { formatYearMonth } from "../lib/format";
 
 export interface MonthTitleProps {
-    yearMonth: number;
+    year: number;
+    month: number;
 }
 
-export const MonthTitle:FC<MonthTitleProps> = ({yearMonth}) =>
-<div className="divider text-2xl">{`${formatYearMonth(yearMonth)}`}</div>
\ No newline at end of file
+export const MonthTitle:FC<MonthTitleProps> = ({year, month}) =>
+<div className="divider text-2xl">{`${formatYearMonth(year, month)}`}</div>
\ No newline at end of file
diff --git a/app/year-month/[id]/add/page.tsx b/app/year-month/[id]/add/page.tsx
index fef23e4..ed28252 100644
--- a/app/year-month/[id]/add/page.tsx
+++ b/app/year-month/[id]/add/page.tsx
@@ -1,10 +1,12 @@
-import { addYearMonth } from '@/app/lib/actions/yearMonthActions';
+import { addMonth } from '@/app/lib/actions/monthActions';
 import { revalidatePath } from 'next/cache';
 import { redirect } from 'next/navigation';
 
 export default async function Page({ params:{ id } }: { params: { id:string } }) {
 
-    await addYearMonth(id);
+    const [year, month] = id.split("-");
+
+    await addMonth(year, month);
 
     revalidatePath('/');
     redirect(`/`);