Coming off August in which they finished modestly lower, gold-backed exchange traded funds could use the benefit of some favorable seasonality.

That is exactly what the likes of the SPDR Gold Shares (NYSEArca: GLD) and ETFS Physical Gold Shares (NYSEArca: SGOL) could be in for in September. The relief of favorable seasonality comes with GLD and friends flirting with two-month lows.

“September is the hottest month of the year for gold prices,” according to ZeroHedge. Over the past 20 years, gold has posted a 3% gain in the month of September, nearly double the yellow metal’s average November performance. November is the second-best month for gold prices over the past 20 years.

“Buying typically increases with India’s festival period, which runs from late August to October and is followed by the wedding season, times when bullion is bought for part of the bridal trousseau or in jewelry form as gifts from relatives. Chinese purchases may also increase toward year-end, before the country’s Lunar New Year celebration in February,” reports Nicholas Larkin for Bloomberg.

China and India are the two largest gold consumers in the world, with the former having replaced the latter in the top spot last year. However, there are possible stumbling blocks to another bullish September for gold and gold ETFs.

There are signs demand is waning in China and Indian demand is expected to falter by as much as 13% to 850 metric tons this year, the lowest level since 2009, due to the country’s tariff on bullion imports implemented last year as a means of cutting a widening current-account deficit. [Gold ETFs Lose Predictive Power]