What does the 200-day moving average mean?
Add up the last 200 daily closes and divide by 200: that is the 200-day simple moving average (SMA), and by convention “the 200-day” means the simple one; moving averages explained shows the arithmetic. A US trading year has about 252 sessions, so 200 sessions are roughly 40 weeks, or nine and a half months. On a weekly chart the closest match is the 40-week average.
It is a slow line on purpose. Each day one close enters the window and the oldest leaves, and the average moves by the difference divided by 200. Hypothetical: if XYZ closes $10 above the close dropping out, its 200-day rises by only $0.05. That is why investors watch it: one bad week barely moves it, so its slope shows the trend of most of the past year.
Two readings matter most: which side of the line price is on, and which way the line slopes. In the drawing at the top, green marks stretches where the hypothetical index was above a rising 200-day, red where it was below a falling one, and white where the two disagreed.
- 200-day moving average
- The average of the last 200 daily closes, about 40 weeks, usually a simple average. Price above a rising 200-day is a common definition of a long-term uptrend.
What does the 50-day moving average show, and what if the 50 is below the 200?
The 50-day moving average covers about 10 weeks, or two and a half months, so it follows the medium-term trend and turns well before the 200-day. Swing traders and growth investors often treat it as the first line a pullback in an uptrend should hold; best moving average settings compares the common lengths by trading style.
When the 50-day is below the 200-day, the last 10 weeks have averaged less than the last 40: the trend has been weak or falling. The day the 50-day crosses below the 200-day is called a death cross, and crossing back above a golden cross; both arrive late by design, as the moving average crossover lesson shows. In the drawing, the death cross printed 36 sessions after the top, with the index already 13.1% below it.
- 50-day moving average
- The average of the last 50 daily closes, about 10 weeks: a medium-term trend line that turns well before the 200-day.
Simple or exponential 200-day moving average: which one?
The simple 200-day is the convention: it is what most financial news, stock screeners and the classic golden cross use. A 200-day exponential moving average (EMA) gives the newest close a weight of about 1%, more than the simple average’s 0.5%, so it sits closer to price and turns sooner. Neither is more correct, as types of moving averages explains: the SMA is the line more people watch, the EMA the one that reacts a little faster.
The difference shows most after a sharp fall. In the drawing below, the same hypothetical index dropped 28.7% from its top and then recovered in a V. After the low, it took 39 sessions to close above its 200-day EMA, by then 22.0% off the low; 42 sessions to close above its 200-day SMA, 25.6% off the low; and 78 sessions for the golden cross, 27.5% off the low.
How do investors and traders use the 200-day moving average?
Mostly as a filter, not as a buy or sell signal on its own. Hypothetical: XYZ has risen for a year and its 200-day SMA, now $88.00, is still climbing. Price pulls back from $104 to $89.20, holds above the line for three sessions and closes at $91.50 after a strong day. A trader who uses the 200-day as a pullback zone might buy at $91.50 with a stop under the pullback low at $87.40, risking $4.10 a share; with $200 at risk, that is 48 shares. If XYZ then closes below the line and the line flattens, the zone has failed. The common uses:
- Trend filter: buy only stocks above a rising 200-day and skip longs below a falling one. Stage analysis applies the same idea to a weekly chart with a 30-week average.
- Market regime: many traders check whether the index itself, or an ETF that tracks it such as SPY, is above its 200-day before sizing up, and trade smaller below it. UpTickFlow’s optional market filter, off by default, uses this idea: it shows BUY signals only while SPY’s last daily close is above its 200-day average.
- Pullback zone: in a long uptrend, a first pullback to a rising 200-day is watched as a zone, like any support and resistance level, with the stop below the swing low.
- Higher-timeframe check: a short-term trade taken in the direction of the daily 200-day, the same idea as the EMA trading strategy.
- Trend filter
- A rule that allows trades only in the direction of a slower trend measure, such as buying only while price is above a rising 200-day average.
Stocks above their 200-day moving average: a breadth gauge
Count how many members of an index trade above their own 200-day average and you get one of the simplest breadth indicators. On TradingView, the symbol S5TH, “S&P 500 Stocks Above 200-Day Average”, tracks it for the S&P 500. Readings above 50% mean most stocks are in long-term uptrends; market breadth covers the conventions and the other breadth tools.
Its main use is a mismatch between the index and its members. In the drawing below, a hypothetical index of 40 stocks, in which 4 large stocks carry half the weight, rose 42% while the share of its stocks above their 200-day fell from 80% to 30%. At the end, all four large stocks were above their 200-day and only 8 of the other 36 were: a new high carried by a few.
Does a 200-day moving average strategy work? What the research says
Simple moving-average rules are among the most tested ideas in finance. Brock, Lakonishok and LeBaron (Journal of Finance, 1992) tested moving-average rules, including price against its 200-day average, on the Dow Jones index from 1897 to 1986, and found that buy signals were followed by higher returns than sell signals. Moskowitz, Ooi and Pedersen (2012) found that returns in 58 futures markets tended to persist for one to 12 months before partly reversing, the kind of behaviour a slow trend filter relies on.
The caveats matter as much as the findings. When Sullivan, Timmermann and White (1999) widened the test to thousands of rules on a century of Dow data and corrected for data snooping, the best rule’s edge did not hold up in the following decade. A 200-day filter is a way to stay with long trends and step aside in long declines, not a forecast; does technical analysis work? puts these studies in context.
The limits: whipsaws and lag in V-shaped recoveries
Lag is the price of smoothness. In the V-shaped recovery above, the golden cross came 78 sessions after the low, with the index already 27.5% higher, and the death cross had come only after a 13.1% fall from the top. A 200-day rule gives up the first part of every new trend and sits through the first part of every decline.
Whipsaws are the other cost. When price moves sideways around a flat 200-day, it crosses back and forth: in the same hypothetical index, price closed on the other side of its 200-day SMA eight times in 360 sessions, five of them within 12 sessions as the index recovered. Common fixes are waiting for a close a few percent beyond the line, checking only at the end of each week or month, or requiring the line itself to slope your way. Each removes some whipsaws and makes every signal later, and frequent switching adds costs.