As the gold market makes an impressive bull run this year, precious metals exchange traded fund (ETF) investors will have to watch a handful of factors to gauge how far the rally can keep going.

Year-to-date, the SPDR Gold Shares (NYSEArca: GLD), iShares Gold Trust (NYSEArca: IAU) and ETFS Physical Swiss Gold Shares (NYSEArca: SGOL) have returned over 21%.

Comex gold futures were hovering at around $1,287.8 per ounce Tuesday and briefly traded above $1,300 per ounce, a 15-month high.

As gold bugs root for an extended rally, traders will have to monitor the Federal Reserve, the U.S. dollar, investment demand, China & India and a potential Brexit for further cues on where the bullion is heading, writes Henry Sanderson for the Financial Times.

The bullion was depressed last year ahead of the Federal Reserve’s first interest rate hike in almost a decade. However, with the Fed signalling a more cautious monetary policy amid sluggish growth, gold is finding further support from a prolonged low-rate environment. Nevertheless, if the Fed does hike rates, investors will have to look to real interest rates.

“Even if you have a situation where the Fed does raise rates two or three times but inflation has already taken root real rates can remain low or even negative so there’s no reason that gold can’t move higher,” James Luke, a fund manager at Schroders, told the Financial Times. “Particularly with the amount of negative yielding assets in the investment universe and serious concerns over post-QE stock market health.”

[related_stories]

Gold has been strengthening as an alternative asset to the depreciating U.S. dollar – as the USD weakens, gold becomes cheaper for foreign investors and also acts a better store of wealth. Moreover, global central banks have been cutting interest rates, which have weighed on their respective currencies.

“There’s a gradual loss of confidence in central banks’ ability to help or control the economy or control the money supply and gold is a form of money so it competes with other forms of money for consumers,” Jim Rickards, author of The New Case for Gold, told the Financial Times “As you begin to lose confidence in central bank money, that leads to increased interest in gold.”

Demand for gold assets have surged this year. For instance, ETF flows into gold have expanded at their fastest pace since 2009. Physically backed gold ETF holdings are still one-third below the December 2012 peak, which suggest that prices can hold at about $1,200 per ounce.

However, emerging market demand for gold has not picked up yet. For instance, China has shown little demand, with the Shanghai Gold Exchange seeing little growth in volume. While the higher prices may have deterred Asian buyers, demand could pick up if prices persist in going higher, analysts said.

Lastly, a Brexit will trigger greater volatility and push more toward gold as a safety play. According to HSBC, gold could benefit from a “sizeable safe haven bid,” attracting some of the capital outflows form the pound and euro.

Click here to read more ETF news, strategy and commentary on ETF Trends.