Showing daily action of the 2018-2022 S&P 500, adding more detail of market action, which seems pretty interesting to me.
The S&P 500 is a weighted index representing the capitalization value of the 500 largest U.S. companies.
Then all of the S&P 500 Index mutual funds track it with similar percentage numbers (less fund fees).   ( A good S&P 500 graph )

The market goes up and down every day. So don't sweat the small stuff, think long term, but this table does show the past S&P 500 action. It can be volatile and has some bad times, which are "lost time" for earnings, but it always recovers, and overall performance is good and certainly worthwhile.

• 2018 was Not a good year. December 24 was down 20%, with year ending down at -6.24% (if not including the +2.09% dividend). But it recovered (7 months between the adjacent record highs). Only 19 record highs in 2018.
• 2019 had a slow start (recovering from end of 2018), but then 35 record highs with 28.88% year end gain.
• 2020 was the March pandemic crash (-34%). But it recovered (6 months between the adjacent record highs). Not a great year, but not bad at all. 33 record highs and 16.25% year end gain.
• 2021 was another great year, 70 record highs and 26.89% gain.
• 2022 is the oil and inflation and Ukraine and other current worries piling up now. So far, the S&P 500 had only one new record high on the first market day of year, but was down -23% from year end on June 16. It has always recovered. This time may be slower, but times will get good again. The US mid-term election is November 8, 2022.

The gains in this table are from daily S&P 500 prices, which in themselves do Not include dividends or compounding. The price gain alone of the four full years 2018-2021 of the S&P 500 was 78.27%, but the the Total Return earned 91.34% gain (near double value), through the good and bad times. For comparison, that Annualized Total Return was as if it had earned about 17.6% fixed income every year for four years (which if banks ever paid that, it would be the same overall result). And with more years (longer term), compounding will grow to easily become the largest part of gain.

Here is a calculator to see other values:

Compute Compounded Gain and Annualized return

Percentage gain =

New value - Old value
Old value

× 100

New value from Old over years

Any units (like feet or weight). Gain need Not be money.
Years can be blank if annualized return not needed.
Any $ or , format keys are optional, and are ignored.

Annualized return includes the long term compounding of several years, and is a hypothetical number computed to be AS IF the same final result instead resulted from a Fixed equal gain, same every year. This Annualized gain rate purpose is for comparisons (with banks and other fixed rate interest), and it computes the fixed gain rate that would match the same market compounded result. (The initial default case indicates that 1.11623¹⁰ = 3.000x value, from 1x value.) It hides any volatility during the years, computing a smooth path that would give the same result in the same time.

See annual S&P Total Return detail in a 50 year S&P 500 Calculator.
See 15 years of 60+ individual stock and fund histories compared.

Table Color Legend: