Glossary

Single Print

Also called: single TPO · single-print gap · tail

How a single print is made

A TPO profile stamps one letter at every price traded during each 30-minute period. Most prices collect several letters. A price touched in one period and never again carries exactly one, and that is a single print — a statement about time, not about volume.

The distinction matters. A price can absorb enormous size in ninety seconds and still be a single print, because only one period touched it. A single print and a low volume node therefore coincide often without being the same object: one counts periods, the other counts contracts. Where they disagree, the volume profile describes what actually traded.

At the extreme, it is excess

Single prints at the top or bottom of a profile form a tail: price probed, found nothing, and left fast enough that no later period returned. That tail is the auction's own full stop. It says the market tested a price and refused it, rather than simply running out of participants.

An extreme with no such tail carries the opposite reading — a poor high, an auction that stopped without finishing.

Inside the profile, it is a thin shelf

Interior single prints mark prices the market crossed in a hurry, usually on a break out of balance. Later trade tends to return and stamp more letters across them, because a price that was rushed through was never properly auctioned. That is the honest version of single prints get filled: a description of how profiles accumulate, not a rule with a hit rate.

A worked example

In a synthetic ES session profiled on 30-minute periods, the top four prices — 5 348.25 through 5 349.00 — carry a single letter each, above a first two-letter price at 5 348.00. That is a four-tick buying tail. Two sessions later in the same synthetic series, trade returns and stamps three periods across 5 348.25 to 5 348.75, leaving one tick of the original tail intact.

Lower in that same profile, 5 331.50 and 5 331.75 are also single prints, crossed in under a minute on the move out of the morning range. They sit in the middle of the day's business rather than at its edge, and carry no rejection information at all. Same construction, opposite meaning, decided entirely by location.

Frequently asked

What is the difference between a single print and a low volume node?

A single print counts time: one TPO period touched that price. A low volume node counts contracts: little traded there. A two-minute spike on heavy size prints one letter and a fat volume row at once, so the two readings can point at different prices within the same session.

Do single prints always get filled?

No, and no published dataset puts a number on how often they do. Many are revisited because profiles naturally accumulate around prices the market rushed through, some are never touched again, and none of them arrive with a deadline attached.

Does the period length change which prints are single?

Yes. Thirty minutes is a convention inherited from the floor, not a property of the market. Halving it produces more single prints, doubling it produces fewer, and both profiles are built from exactly the same trades. Fix the period before you record anything.

Related terms

• TPO (Time Price Opportunity) — one mark showing that a price traded during one half-hour bracket — a measure of time, not volume
• Market Profile — price and time organised into a distribution of letters, one per half-hour a price traded
• Low volume node (LVN) — a pinch in the profile where the auction was cut short — crossed fast, or rejected cleanly
• Poor High / Poor Low — a flat profile extreme with no excess, the sign of an auction that stopped without finishing