Nov 30 (Reuters) - Australian shares opened higher on Monday, and were on track to post their biggest monthly gain, as optimism surrounding COVID-19 vaccine candidates and hopes of an economic recovery in the coming year boosted risk appetite. The S&P/ASX 200 index was up 0.5% at 6,632.90 by 2330 GMT. It was on track to add nearly 12% in November, its biggest monthly gain on record. Optimism around multiple potential effective coronavirus treatments buoyed global stock markets this month, with hopes of a swift economic recovery in 2021 further bolstering the gains. Investors will be eyeing third-quarter gross domestic product data due on Wednesday that is expected to show a rebound in the economy - a likely 2.5% growth in September quarter from a 7% contraction in the June quarter, according to a Reuters poll. “With another solid gain likely in Q4 and the growth outlook looking positive for 2021, GDP could be back to its pre-pandemic level sometime in 2021,” analysts at ANZ said in a note. Heavyweight financials sub-index gained 0.5% on the back of blue-chip banking stocks, with the sector on track to post a record monthly gain of more than 17%. Miners were set to post their best month since May, while energy companies were poised to add more than 30% in November, their record monthly gain. Meanwhile, an 11.8% fall in Treasury Wine Estates weighed a little on the index after the winemaker said it would redirect some wine intended for China and cut costs after Beijing imposed anti-dumping tariffs on Australian wine. In New Zealand, the benchmark S&P/NZX 50 index rose 0.5% to 12,703.12, on track to add more than 5% in November, likely its second consecutive monthly gain. Reporting by Sameer Manekar in Bengaluru, Editing by Sherry Jacob-Phillips