If you are still scrambling to get your tax filings ready for Uncle Sam, be sure to remember that commodities-related exchange traded fund positions are not taxed liked other assets.

ETFs track a basket of securities, and investors are taxed based on the type of underlying assets they are exposed to. Most investors will file taxes on short-term gains, which are taxed at one’s ordinary income rate at a maximum 39.6% for single filers, and on long-term gains, which for most comes at 15%, reports John Waggoner for USA Today.

However, if an ETF is backed by physical bullion, such as the SPDR Gold Shares (NYSEArca: GLD), the government sees the precious metals ETF as a physical investment, so physically backed ETFs are taxed as a collectible, with a maximum capital gains rate of 28%.

On the other hand, commodity ETFs that hold futures contracts, such as the popular the United States Oil Fund (NYSEArca: USO), which tracks West Texas Intermediate oil futures, follow a so-called 60/40 tax regiment. Specifically, futures-based ETFs have a 60% long-term gains and a 40% short-term gains, regardless of how long an investor has held onto these ETFs.