Educational reference. Measured from 69 recorded 15m bars of MES (Micro E-mini S&P 500) on Friday, September 18, 2026.
RSI crossed above 70 2 separate times during the session, and the typical visit lasted 157 minutes. Across the whole session it sat above 70 for 30.4% of the time, between 30 and 70 for 63.8%, and below 30 for 5.8%.
| Band | Share of session | Bars | Separate visits | Median visit | Longest visit | |
|---|---|---|---|---|---|---|
| Above 70 | 30.4% | 21 | 2 | 157 min | 255 min | |
| Between 30 and 70 | 63.8% | 44 | 4 | 165 min | 315 min | |
| Below 30 | 5.8% | 4 | 3 | 15 min | 30 min |
RSI compares the size of recent gains with recent losses, so a reading above 70 says buying has dominated the last 14 bars — not that price is high. A long stay above 70 is a market trending up, which is the opposite of the reversal the word 'overbought' suggests.
Here the reading entered overbought territory 2 times, with a median stay of 157 minutes and a longest of 255. A brief excursion above 70 that resolves in minutes is noise on this timeframe. A sustained one is the signature of a trend that is still running, and selling into it is how traders get run over.