Question

Answer

In Market Profile charts, "singles" refer to prices within profiles which only contain a single TPO/letter but which are surrounded (above and below) by prices with at least two TPOs.  If you look at the market profile chart to the right, notice that singles were created in the N period, as those singles have double TPOs both above and below them.  However, if you look at the P at extreme low of the profile, that is not considered a single because there are no prices below it which contain 2 or more TPOs.

Given this definition of "singles", and based on user feedback, when singles are taken out (when the current price moves to touch a single from a previous profile that had not currently been touched since it's creation), then it is theorized that price will commonly continue to the extreme price of the profile in which the single was created.  Therefore, singles are labelled with the extreme price of the profile in which the single was created.  That extreme price will be the high price of the profile if the single was made on the way down, and the low of the profile if single was made on the way up.  NOTE: Singles within the current/rightmost profile will be labelled with their actual price, and not the extreme price.  The label will change to the extreme price once the next profile begins, as the extreme price is only relevant in future profiles.  ADDITIONAL NOTE:  As of version 10.0, an option has been added to the Price Levels tab of the Market Profile preferences window titled "Label Singles with Extreme Price of Profile".  If this option is not checked, all singles will be labelled with their actual price.

Notice in the chart to the right, that singles were created on the way down in the N period.  While there are technically 5 single prices, the highest single made on the way down is the key single.  If singles are created on the way up, the lowest key single is the one with the lowest price.  And since this single is made on the way down, it is labelled with the high price of the profile (which happens to be 779.00).  It is believed that if price returns to 760.00 during a subsequent profile ("takes out" the single), then price will continue to the  high (779.00) of the profile in which it was created.