1973
... that prior to Singapore's first Formula One race in 2008, the last running of the Singapore Grand Prix was as a non-championship race run to Australian Formula Two rules in 1973?
... that prior to <a href="./Singapore" id="mwAug" rel="mw:WikiLink" title="Singapore">Singapore</a>'s first <a href="./Formula_One" id="mwAuk" rel="mw:WikiLink" title="Formula One">Formula One</a> race in <a href="./2008_Singapore_Grand_Prix" id="mwAuo" rel="mw:WikiLink" title="2008 Singapore Grand Prix">2008</a>, the last running of the <a href="./Singapore_Grand_Prix" id="mwAus" rel="mw:WikiLink" title="Singapore Grand Prix">Singapore Grand Prix</a> was as a non-championship race run to <a href="./Australian_Formula_2" id="mwAuw" rel="mw:WikiLink" title="Australian Formula 2">Australian Formula Two</a> rules in <b id="mwAu0"><a href="./1973_Singapore_Grand_Prix" id="mwAu4" rel="mw:WikiLink" title="1973 Singapore Grand Prix">1973</a></b>?