Percent above moving averages, and new highs vs new lows
Lesson 9 · about 10 min
The A/D line tells you direction of participation. Two other daily series tell you the condition of the average stock: how many are in uptrends, and how many are at fresh extremes. Between them they give you an oversold/overbought read on the whole market that no index chart can.
Percent of stocks above a moving average
For a given index, count the members trading above their 50-day (or 200-day) simple moving average and divide by the number of members. The result is a percentage between 0 and 100.
| Series | Measures | Speed |
|---|---|---|
| % above 20-day MA | Very short-term participation | Fast |
| % above 50-day MA | Intermediate trend health | Medium |
| % above 200-day MA | Long-term trend health | Slow |
The 50-day version is the workhorse for swing traders. Rough zones on the S&P 500, treated as starting points:
100% ┤
90% ┤ ▓▓▓▓ overbought; rallies often pause, but strong trends live here for weeks
80% ┤ ▓▓▓▓
70% ┤ ░░░░ healthy uptrend
50% ┤ ──── neutral / mixed
30% ┤ ░░░░ weak
20% ┤ ▓▓▓▓ oversold; historically many swing lows form here
10% ┤ ▓▓▓▓ washout
0% ┤
Three ways to read it:
Level for condition. Below 20% on the 50-day means four stocks in five are in short-term downtrends. That is the kind of washed-out condition where bounces start, though "start" can mean next week rather than tomorrow.
Divergence at highs. Index at a new high with the % above 50-day at 55% when it was 80% at the previous high is the narrowing story again, from a different angle.
Crosses for regime. Some traders define the swing regime by the 50-day version: above 50% and rising is a long regime; below 50% and falling is a short or cash regime. Crude, but a crude filter that is applied is worth more than a subtle one that is not.
The 200-day version is a longer regime measure. Readings above 70-80% have marked healthy bull markets; sustained readings below 30% have marked bear markets; readings under 15% have appeared near major lows (2008-09, March 2020, autumn 2022 are recent examples), though never on a schedule.
Key idea: Percent above the 50-day is an oscillator for the whole market. Extremes mark exhausted conditions on both sides, and divergences at index highs mark narrowing. Use it to grade the regime and to avoid buying breakouts at 90% or shorting breakdowns at 10%.
New highs vs new lows
Each day the exchanges report how many stocks made a new 52-week high and how many made a new 52-week low. Net new highs = highs minus lows.
| Condition | Reading |
|---|---|
| New highs expanding, new lows near zero | Healthy uptrend |
| Index at high, new highs fewer than at last high | Narrowing; leadership thinning |
| New highs and new lows both elevated | Split market; often precedes volatility |
| New lows expanding, highs near zero | Downtrend |
| New lows spike then contract while index flat | Selling exhaustion; watch for a low |
The third row is the origin of the "Hindenburg Omen", a signal that fires when both highs and lows are elevated at the same time. Its record as a crash predictor is poor; it fires far more often than crashes occur. The underlying observation, that a split market is an unstable one, is sound. The specific omen is not a trading rule.
A cumulative net new highs line (add each day's highs minus lows) behaves like a slow A/D line and is useful for the same divergence reads.
The washout pattern
The single most useful new-lows pattern for swing traders:
Day: 1 2 3 4 5 6 7 8 9 10
New lows: 180 260 410 620 390 210 150 140 90 60
Index: ─╲ ╲ ╲ ╲╲ ╲ ─ ─ ╱ ╱ ╱
▲ peak in new lows
▲ index low, on fewer new lows
New lows peak on day 4 with the sharpest index decline. The index then goes lower (or retests) on days 5-7 with far fewer new lows. Fewer stocks are breaking down on each push; the selling is exhausting. This positive divergence in new lows has preceded many swing bottoms and is usually clearer than the equivalent in the A/D line.
It is not infallible. In a bear market it can print several times before the real low. Use it to lower short size and prepare long setups, not to buy blindly.
Combining the two
| % above 50-day | Net new highs | Regime read |
|---|---|---|
| > 70%, rising | Positive, expanding | Broad uptrend; long breakouts favoured |
| > 70%, falling | Positive but shrinking | Late in the swing; tighten |
| 40-60% | Mixed | Rotation or range; stock-specific |
| < 30%, falling | Negative, expanding | Downtrend; short setups favoured |
| < 20% | Negative but peaked | Washout; prepare for a bounce |
You will notice this is the daily-timescale version of the trend/chop/reversal table from Module 2. The same logic applies: one series describes, two confirm, disagreement is information.
Sources and index choice
These series are published for the S&P 500, Nasdaq 100, Russell 2000 and the exchange composites. Use the one that matches what you trade. A small-cap trader checking S&P 500 breadth is reading the wrong room. Module 6 lists where each is available free.
Try it: Find the % of S&P 500 stocks above their 50-day MA for the last three years. Mark every reading below 20% and every reading above 90%. For each mark, note the index return over the next 10 and 20 sessions. You will find the base rate is asymmetric: lows below 20% tend to bounce more reliably than highs above 90% tend to fall.
Recap
- Percent above the 50-day MA is a whole-market oscillator: above 80-90% is stretched, below 20% is washed out, divergence at index highs is narrowing.
- The 200-day version grades the long-term regime; readings under 15% have appeared near major lows, never on a schedule.
- New highs vs new lows show leadership health; elevated highs and lows together mark an unstable split market, though the "omen" built on it is a poor predictor.
- A peak in new lows followed by an index retest on fewer new lows is a reliable exhaustion pattern for swing lows.
- Use the series for the index you actually trade.
See it drawn
Original diagrams for the ideas on this page. Illustrative, not real market data.