Investors in commodities have been on a huge losing streak in the past few years. 
Jodie Gunzberg, S&P Dow Jones Indices global head of commodities, said in a note that "2015 will go down in history as one of the worst years ever for commodities."
Concerns over the health of the Chinese economy, which is a main demand-driver for commodities, and oil prices falling to record lows helped accelerate the rout last year.
According to Bank of America Merrill Lynch, the current commodities rout is the worst since the Great Depression hit in the 1930s.
Annualised returns for commodities in the past 10 years are -5.1%. It's the first time commodities have lost money over a 10 year period since the 1960s.
Here's the chart:
BAML commoditiesBank of America Merrill Lynch

And here's how other assets measure up for the past 10 years:
BAML CommodsBank of America Merrill Lynch