diff --git a/CHANGELOG.md b/CHANGELOG.md
index ae0c220..5da0df5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,8 @@
+## 0.1.26
+
+fix: missing title_before
+([#28](https://github.com/spacemeowx2/s3si.ts/issues/28))
+
 ## 0.1.25
 
 fix: missing king_smell
diff --git a/src/constant.ts b/src/constant.ts
index 458d99f..d9df823 100644
--- a/src/constant.ts
+++ b/src/constant.ts
@@ -1,7 +1,7 @@
 import type { StatInkPostBody, VsHistoryDetail } from "./types.ts";
 
 export const AGENT_NAME = "s3si.ts";
-export const S3SI_VERSION = "0.1.25";
+export const S3SI_VERSION = "0.1.26";
 export const NSOAPP_VERSION = "2.3.1";
 export const WEB_VIEW_VERSION = "1.0.0-433ec0e8";
 export const S3SI_LINK = "https://github.com/spacemeowx2/s3si.ts";
diff --git a/src/exporters/stat.ink.ts b/src/exporters/stat.ink.ts
index 6dd9242..daf4745 100644
--- a/src/exporters/stat.ink.ts
+++ b/src/exporters/stat.ink.ts
@@ -28,10 +28,17 @@ import {
 } from "../types.ts";
 import { msgpack, Mutex } from "../../deps.ts";
 import { APIError } from "../APIError.ts";
-import { b64Number, gameId, s3siGameId } from "../utils.ts";
+import { b64Number, gameId, nonNullable, s3siGameId } from "../utils.ts";
 import { Env } from "../env.ts";
 import { KEY_DICT } from "../dict/stat.ink.ts";
 
+const COOP_POINT_MAP: Record<number, number | undefined> = {
+  0: -20,
+  1: -10,
+  2: 0,
+  3: 20,
+};
+
 class StatInkAPI {
   FETCH_LOCK = new Mutex();
   cache: Record<string, unknown> = {};
@@ -553,10 +560,32 @@ export class StatInkExporter implements GameExporter {
         defeated_by_me: i.defeatCount,
       }]),
     );
+    const title_after = detail.afterGrade
+      ? b64Number(detail.afterGrade.id).toString()
+      : undefined;
+    const title_exp_after = detail.afterGradePoint;
     const clear_waves =
       detail.waveResults.filter((i) => i.waveNumber < 4).length -
       1 + (resultWave === 0 ? 1 : 0);
 
+    let title_before = undefined;
+    let title_exp_before = undefined;
+    const expDiff = COOP_POINT_MAP[clear_waves];
+
+    if (nonNullable(title_exp_after) && nonNullable(expDiff)) {
+      if (title_exp_after === 40 && expDiff === 20) {
+        // 20 -> 40 or ?(rank up) -> 40
+      } else if (title_exp_after === 40 && expDiff < 0 && title_after !== "8") {
+        // 60,50 -> 40 or ?(rank down) to 40
+      } else if (title_exp_after === 999 && expDiff !== 0) {
+        // 980,990 -> 999
+        title_before = title_after;
+      } else {
+        title_before = title_after;
+        title_exp_before = title_exp_after - expDiff;
+      }
+    }
+
     const result: StatInkCoopPostBody = {
       uuid: await gameId(detail.id),
       private: groupInfo?.mode === "PRIVATE_CUSTOM" ? "yes" : "no",
@@ -568,10 +597,10 @@ export class StatInkExporter implements GameExporter {
       king_smell: smellMeter,
       king_salmonid: this.mapKing(detail.bossResult?.boss.id),
       clear_extra: bossResult?.hasDefeatBoss ? "yes" : "no",
-      title_after: detail.afterGrade
-        ? b64Number(detail.afterGrade.id).toString()
-        : undefined,
-      title_exp_after: detail.afterGradePoint,
+      title_before,
+      title_exp_before,
+      title_after,
+      title_exp_after,
       golden_eggs,
       power_eggs,
       gold_scale: scale?.gold,
diff --git a/src/utils.ts b/src/utils.ts
index bbb5e52..e0babf0 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -159,3 +159,7 @@ export function b64Number(id: string): number {
   const [_, num] = text.split("-");
   return parseInt(num);
 }
+
+export function nonNullable<T>(v: T | null | undefined): v is T {
+  return v !== null && v !== undefined;
+}