first housed the colonial governor. The entire national anthem's lyrics are included as microprint, which is a unique feature to the banknote. $10,000 banknote The onyx cowrie is featured on the obverse background of the banknote. Its reverse carries the theme of economy featuring Singapore as a knowledge-based economy – biotechnology, R&D and silicon wafer. Yusof was a businessman who started the first Malay newspaper for the masses, Utusan Melayu. It was one of the highest-value banknote in the world in terms of absolute value (worth approximately US$7,250 as of July 2022) that was in public circulation. Commemorative banknotes Millennium banknote In celebration of the Millennium 2000, five million bills were printed with the Millennium 2000 logo replacing the prefix of the serial number normally found in other notes under general circulation. Overprinted banknotes Three commemorative limited issues have been made for the Portrait Series (including the issue below). 10,000 sets of the polymer was issued with the overprint 'Commemorative First Issue by MAS' with the prefix MAS. 5,000 sets of banknotes signed by PM Lee Hsien Loong have been stamped with overprint commemorating the merger of the BCCS and MAS. $20 banknote On 27 June 2007, the governments of Singapore and Brunei celebrated the 40th anniversary of the Currency Interchangeability Agreement (an agreement allowing citizens of both countries to use currency from either nation interchangeably) by issuing commemorative notes, that are yellow, 149 × 72 mm in size, and made of polymer. The obverse of the Singaporean version is similar to the current Portrait Series, whereas the obverse of the Brunei version is similar to the and of the 2004 series. The reverses are almost identical except that the Brunei version has their state title in Jawi script, while the Singaporean version has the state title of Brunei in Latin script. A limited edition set was offered for sale, which consisted of both versions in a folder, with matching serial numbers. The notes have "40th Anniversary Currency Interchangeability Agreement" overprinted on the obverse side. In addition, the Singaporean version has the two countries' state crests above the commemorative text. Only 12,000 sets were available, 10,000 from the Monetary Authority of Singapore, and 2,000 from the Brunei Currency and Monetary Board. The circulation version was made available from 16 July 2007. SG50 banknotes Five and one polymer commemorative banknotes were made available from 20 August 2015. They are part of