A late‑week selloff left the S&P 500 on weaker footing heading into the new week.

MarketWatch data (last updated Mar. 20, 2026, 5:05 p.m. EDT) showed the S&P 500 Index (SPX) closing at 6,506.48, down 1.51% on the day.

The same snapshot listed:

• Five‑day performance: -1.90%

• One‑month performance: -5.83%

• Year‑to‑date performance: -4.95%

• 52‑week range: 4,835.04 to 7,002.28

On the session, the index opened at 6,594.66 and traded in a day range of 6,473.52 to 6,594.66, according to MarketWatch.

While the index‑level move sets the tone, sector and single‑stock shifts can matter just as much for portfolios. MarketWatch’s S&P 500 page also highlighted a mix of winners and laggards among index constituents.

Looking ahead: The next trading sessions will determine whether the pullback extends or stabilizes, with many investors monitoring forthcoming macroeconomic releases and company updates.