The Trade Desk has had a terrible 2025. Will it rebound in 2026?The Trade Desk (TTD 1.04%), a former highflying digital advertising disruptor, has fallen on hard times this year.Just how hard? The former market darling is neck and neck with financial stock Fiserv as the worst-performing stock in the S&P 500 Index in 2025, having shed 66.2% of its value this year through Dec. 9. A decline like that could portend longer-term secular problems, but could also signal a buying opportunity. So, which is it for the ...