The SPDR S&P 500 ETF Trust is on track to finish an unpredictable 2021 near record highs after a third consecutive year of 16 percent-plus gains for the market. But with inflation concerns lingering and uncertainty surrounding the ongoing pandemic, there are plenty of reasons for investors to be concerned about stretched stock market valuations heading into 2022. Here are eight market themes traders should look for in 2022. 1. Diversification and Defense Investors looking to protect their portfolios against an uncertain environment may try to diversify outside of the tech-heavy growth stocks that have performed so well since the early 2020 market crash. “Static allocations to passive exposures in fixed income and equities are not advisable in this environment while expanding your portfolio toolkit to include inflation-sensitive assets such as commodities and property are recommended, given their inflation linkages,” Kej Somaia, co-head of Multi-Asset Solutions, recently said. In recent months, …