What is RCI?
The Rank Correlation Index ranks the last 12 closes from highest to lowest and the same bars from newest to oldest, then measures how well the two orders agree. If the newest bar is the highest, the one before it the second highest and so on, the reading is +100. A perfectly falling sequence reads -100, and a jumbled one reads near 0. It is drawn in its own pane with a dashed zero line.
RCI uses only the order of the closes, not their size. It does not measure how far price has moved, and one large bar cannot pull it further than one small bar in the same position.
How to use RCI
- Sign. Above zero the closes have generally risen with time, below zero fallen. Zero is no consistent order.
- Near the extremes. Readings close to +100 or -100 mean almost every bar has continued the sequence. Traders often watch for the line turning back from these zones as a move matures.
- Order, not size. A slow, orderly drift can score as high as a steep rally, so RCI shows consistency of direction rather than speed.
- Length. A short window flips between extremes quickly; a longer window needs a sustained sequence to reach them.
These are ways to read the line, not entry signals on their own.
Settings
| Setting | Default | What it changes |
|---|---|---|
| Length | 12 | Bars in the window being ranked. Lower reaches the extremes and turns faster; higher is steadier. Minimum 2. |
| Source | Close | Which price each bar contributes. Open, high, low and the averaged sources such as hl2 and hlc3 are also available. |
Adjust the window length and price source in the indicator settings.
Calculation
Each bar in the window gets two ranks, and the indicator scores how far apart they are:
time rank = 1 for the newest bar, 12 for the oldest
price rank = 1 for the highest close in the window
d = time rank - price rank, for each bar
RCI = 100 * (1 - 6 * sum of d^2 / (n * (n^2 - 1)))
with n = 12The two rankings run in opposite directions in time and price, newest first and highest first, which is what makes a clean uptrend score +100 rather than -100.
Equal closes share the same rank, set by how many closes in the window are strictly higher. No further adjustment is made for ties, so a window with many identical closes can read slightly differently from a tie-corrected version.
The line starts only once the window holds a full 12 bars; there is no partial reading during warm-up. The dashed zero line is drawn by Altrady Charts as a reference; the indicator itself defines no levels.
Limitations
- It ignores magnitude. It cannot tell a small move from a large one, so a high reading is no guide to the size of the trend.
- It can sit at an extreme for a long time. In a steady trend the reading can stay near +100 or -100 for many bars, so an extreme is not on its own a reversal signal.
- Short windows are jumpy. With few bars, one bar out of order changes the reading by a large amount.
- The live candle moves. The current bar's value changes until that bar closes, and its rank can change every bar of the window.
- It depends on timeframe and length. The same market can be orderly over 12 bars on 1D and random over 12 bars on 5m.
Frequently asked questions
The Rank Correlation Index, or RCI, is the Spearman rank correlation between price and time, scaled from -100 to +100. It shows how consistently the closes in the window rise or fall in order, ignoring how big each move was.
Both correlate price with time. The [Trend Strength Index](/library/indicator/trend-strength-index) uses the actual prices, so a single outsized bar affects it. RCI uses only their order, so a single large bar counts the same as a small one in the same position, and a gentle drift scores as well as a steep one.
Above zero is a rising order, below zero a falling one. Readings near +100 or -100 mean the sequence has been almost perfectly consistent. Traders often watch for the line turning back from those extremes, or crossing zero, as signs a move is losing its order. Test any rule on your own market before relying on it.
Yes. The indicator declares two inputs: Length, default 12 with a minimum of 2, and Source, default close. Open the indicator's settings on the chart to change them. Source accepts any of the available prices, including open, high, low, hl2 and hlc3.
No. Each value is calculated from a fixed window of the latest bars, so closed bars are never revised and loading older history does not change them. The current candle's value moves while it is live and settles when it closes.
Use the Add to chart button at the top of this page. It opens BTC/USDT on Binance in the Altrady Charts terminal with the built-in Rank Correlation Index already applied. On any other market, open the indicator picker on the chart and choose Rank Correlation Index from the Trend group.