By resolution 58/4 of 31 October 2003, the General Assembly designated 9 December as International Anti-Corruption Day. This decision was taken in order to raise awareness of corruption and of the role of the United Nations Convention against Corruption in combating and preventing it.

根據聯合國的'網頁
1209反貪腐日是2003年才訂定的一個日子
聯合國每年都會設定一個主題來宣導
而有些議題則選擇某一天來做
如1201的愛滋日

只是過了6年才來發行郵票
不知其他郵政組織有規劃相同的主題嗎