Bull markets climb a wall of worry, as the old saying goes. The past six years have tested just how high that wall can get.
Source: [MarketWatch](https://www.marketwatch.com/story/why-it-pays-to-stay-invested-no-amount-of-bad-news-could-stop-the-stock-markets-strongest-run-in-more-than-25-years-54ba3f8a?mod=mw_rss_topstories)