A global bond rout coincided with another selloff in chip stocks, this year’s hottest but most rate-sensitive sector. At Tuesday’s close, the PHLX Semiconductor Index was nearing a bear market, down by 18% from its all-time high made back in June but still twice its level a year ago. Chips and bonds seem to have found their footing, for now at least, and stock futures point to a muted U.S. open overall.

With 1,000 exchange-traded funds launched just last year in the U.S., investors can own almost anything they want. Increasingly, that includes funds missing some ingredients they’d rather avoid. Is it a good idea? We know most stocks don’t do very well. Since picking future Nvidias is so hard, efficient market advocates advise just owning them all while paying as little as possible.

Most investors agree. The three largest U.S. ETFs by assets all track the S&P 500, and the fourth is Vanguard’s even broader Total Stock Market ETF with 3,500 stocks and a tiny expense ratio of 0.03%. A bit farther down the list sits yet another Vanguard fund that casts the widest possible net, owning 10,000 stocks globally. But what if you have a hunch that one group will be a drag, or if you have ethical or religious reasons not to profit from certain businesses?