RSI (relative strength index)
A 0-100 momentum oscillator; traditionally above 70 is overbought and below 30 oversold. Divergences are the more valuable signal.
In strong trends RSI can stay in the extreme zone for a long time; the "sell above 70" approach loses money in a trend. RSI failing to make a new high when price does (bearish divergence) shows loss of momentum.
The standard period is 14. RSI is not an entry signal on its own, but a confirmation tool that accompanies structure and level analysis.
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