diff --git a/package.json b/package.json
index 6b5af1d..571830a 100644
--- a/package.json
+++ b/package.json
@@ -28,7 +28,7 @@
     "chart.js": "^2.7.1",
     "classnames": "^2.2.6",
     "cross-env": "^5.2.0",
-    "date-fns": "^1.30.1",
+    "date-fns": "^2.15.0",
     "eslint": "^7.6.0",
     "eslint-config-prettier": "^6.11.0",
     "eslint-plugin-jquery": "^1.5.1",
diff --git a/resources/assets/js/user/stats.ts b/resources/assets/js/user/stats.ts
index f3c0c2a..36ccc02 100644
--- a/resources/assets/js/user/stats.ts
+++ b/resources/assets/js/user/stats.ts
@@ -90,7 +90,7 @@ function createMonthlyGraphData(from: Date) {
 
     for (let i = 0; i < 12; i++) {
         const current = addMonths(from, i);
-        const yearAndMonth = format(current, 'YYYY/MM');
+        const yearAndMonth = format(current, 'yyyy/MM');
         keys.push(yearAndMonth);
         values.push(graphData.monthlySum[yearAndMonth] || 0);
     }
diff --git a/yarn.lock b/yarn.lock
index e39ef96..00585d2 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2562,11 +2562,16 @@ d@1, d@^1.0.1:
     es5-ext "^0.10.50"
     type "^1.0.1"
 
-date-fns@^1.27.2, date-fns@^1.30.1:
+date-fns@^1.27.2:
   version "1.30.1"
   resolved "https://registry.yarnpkg.com/date-fns/-/date-fns-1.30.1.tgz#2e71bf0b119153dbb4cc4e88d9ea5acfb50dc05c"
   integrity sha512-hBSVCvSmWC+QypYObzwGOd9wqdDpOt+0wl0KbU+R+uuZBS1jN8VsD1ss3irQDknRj5NvxiTF6oj/nDRnN/UQNw==
 
+date-fns@^2.15.0:
+  version "2.15.0"
+  resolved "https://registry.yarnpkg.com/date-fns/-/date-fns-2.15.0.tgz#424de6b3778e4e69d3ff27046ec136af58ae5d5f"
+  integrity sha512-ZCPzAMJZn3rNUvvQIMlXhDr4A+Ar07eLeGsGREoWU19a3Pqf5oYa+ccd+B3F6XVtQY6HANMFdOQ8A+ipFnvJdQ==
+
 debug@2.6.9, debug@^2.2.0, debug@^2.3.3:
   version "2.6.9"
   resolved "https://registry.yarnpkg.com/debug/-/debug-2.6.9.tgz#5d128515df134ff327e90a4c93f4e077a536341f"