Macquarie Group H1 net profit falls 43 pct

SYDNEY, Nov 18 (Reuters) - Macquarie Group Ltd (MQG.AX), Australia's biggest investment bank, posted a 43 percent fall in first-half profit after taking substantial writedowns due to sharply deteriorating markets.

Net profit for the six months to end-September fell to A$604 million ($392 million), from A$1.06 billion in the year earlier period, just short of an average forecast of A$607.3 million by six analysts.

Investment banks worldwide have been punished by investors questioning their high-risk business model following the collapse of Lehman Brothers (LEHMQ.PK) and moves by Goldman Sachs (GS.N) and others to become bank holding companies.

Macquarie shares have dived 73 percent this year, while smaller domestic rival Babcock & Brown BNB.AX has lost 98.5 percent, underperforming the broader S&P/ASX 200 index .AXJO, which is down 42.5 percent. (Reporting by Mette Fraende, Editing by Ian Geoghegan)