Materials have been among the best performing areas of the market as the strengthening economic outlook and rising metals prices helped prop up the sector. [Miner ETFs Surge on Improving Metals Prices, Economic Outlook]

Moreover, as risk appetite helps speculative-grade debt strengthen, emerging markets should also benefit from the heightened risk tolerance. For instance, the iShares MSCI BRIC ETF (NYSEArca: BKF), which tracks Brazil, Russia, India and China markets, traded positive in all 10 instances, rising 14% on average, after junk bonds bounced 5% in two weeks. The broader iShares MSCI Emerging Markets ETF (NYSEArca: EEM) and country-focused iShares MSCI South Korea Capped ETF (NYSEArca: EWY) and iShares MSCI Mexico Capped ETF (NYSEArca: EWW) have also been decent plays for a risk-on rally, according to Kensho data.

SPDR Barclays High Yield Bond ETF

Max Chen contributed to this article.