Delayed, Real-Time and Historical Data

“Do you have data?” is not one question. It is at least four, and people who answer it with a single yes end up buying a subscription that cannot do what they wanted, or abandoning a project that free sources could have completed. This lesson separates the products, states what each is documented to provide, and explains why the expensive ones are expensive.

By the end you should be able to say which product answers which kind of question, read a vendor’s offer critically enough to spot what it does not include, and explain why the word “professional” means two entirely unrelated things in this subject.

Four products, one word

Product	What actually arrives	Answers	Cannot answer
End-of-day history	One bar per symbol per session, after the session	What happened over months and years; almost every research question in this course	Anything about the inside of a day
Historical intraday	Minute or second bars for past sessions, delivered on request	How a session unfolded, session structure, opening-range behaviour, replay practice	What is happening right now
Delayed data	Current-session prices, released after a delay set by the venue	What the shape of today looks like; teaching and monitoring	Anything that depends on acting at a price you can still get
Real-time streaming	Updates as the vendor receives them, continuously	What the market is doing at this moment; alerts; live scanning	Anything about the past, unless you also have backfill

The fourth row is the one people mean when they say “real-time data”, and it is the only one that is genuinely expensive. The other three are cheap or free, and between them they cover the great majority of what this course teaches.

Two of them are also independent purchases. Streaming and history are separate products from the same vendor, and a subscription that supplies one does not automatically supply the other. AmiBroker’s plugin documentation makes the split obvious: it describes one provider as supplying no backfill at all, so that with that source the only way to have any history is to import it from somewhere else.

Delayed data

A delayed feed carries real prices, published later than they occurred. The delay period is a condition the venue attaches to redistribution, not a technical limitation and not something your software chooses. Delays are commonly quoted at fifteen or twenty minutes for equities, but the number belongs to each venue and varies between them, so treat the vendor’s own page as the authority for any market you care about.

The important subtlety is that “delayed” does not tell you the shape of the product. In AmiBroker’s own vendor directory, one provider’s delayed offering is annotated “DELAYED, not streaming”, while its real-time offering is annotated “REALTIME, streaming” — two different products, not the same product on a timer. The same vendor’s on-demand product is documented elsewhere in the guide as compatible with third-party software but supplying no streaming quotes at all: historical backfill only, and no tick data.

!Important

Before you buy anything described as delayed, establish two things separately: how long the delay is, and whether the data arrives continuously or only when you ask for it. A delayed snapshot product and a delayed stream behave completely differently inside AmiBroker — the second updates a chart on its own, and the first does not.

For learning, delayed data is genuinely useful and badly underrated. Everything this course teaches about intraday structure — sessions, opening ranges, relative volume, multi-timeframe checks — is just as visible fifteen minutes late. What a delay removes is the ability to act at a price you have seen, and this course stops at the alert anyway.

Real-time streaming

Streaming means the vendor pushes updates to you as they arrive rather than waiting to be asked. What it does not necessarily mean is every update. Interactive Brokers’ documentation describes what Trader Workstation streams as 0.2 to 0.3 second snapshots, and on that basis AmiBroker’s own guidance for that source recommends five-second, fifteen-second or preferably one-minute base intervals rather than tick.

The opposite design also exists, with the opposite problem. DTN’s IQFeed is documented by AmiBroker in capital letters as an unfiltered feed: no tick is filtered out, so you may see a large number of bad ticks. That is not a defect in the vendor’s engineering, it is a deliberate choice to deliver the tape as received and let the recipient decide. It does mean that a database fed by an unfiltered source needs the data-quality habits from Part 2 more, not less.

⌀Data quality warning

Streaming volume is the raw material of your bars, and cleaning it is your problem. Nothing about a feed being live implies it is clean; those are unrelated claims about unrelated properties. Whatever filtering a plug-in offers you, the prints already sitting in your database are unaffected by it, and repairing those is a separate job — a quality scan to find them and the Quote Editor to fix them. Part 18’s IQFeed appendix builds the scan.

Historical intraday

Historical intraday data is what arrives during backfill: when AmiBroker first touches a symbol, the plugin asks the vendor for that symbol’s past bars. How far back it can go is the single most consequential number in a vendor comparison, and it is the number vendors are vaguest about.

What AmiBroker’s own pages document, with the caveat that they contradict one another:

• eSignal — ten days of tick backfill, sixty days of minute bars, roughly ten years of end-of-day, per the vendor directory. Historical requests are documented as throttled by the vendor during the first and last trading hour of the US session, so large loads belong before the open.
• IQFeed — the vendor directory claims ten years of one-minute data, 100 days or more of tick, and twenty years or more of end-of-day. The IQFeed setup page in the same guide says that 100,000 one-minute bars gets you “maximum history available from IQFeed” and describes that as eight months.
• Interactive Brokers — up to thirty days of one-minute backfill, with a maximum of five days per request, and up to 2,000 bars for one-, five- and fifteen-second intervals. Trader Workstation permits only one backfill at a time, and the documentation states a throttle of no more than sixty requests in five minutes, which it illustrates as one month of one-minute data for twelve symbols.
• DDE — no backfill at all, stated twice in capitals. Charts appear only once at least three bars have accumulated, and history has to come from an ASCII import.

?Reality check

Two official AmiBroker pages disagree about IQFeed’s one-minute history depth: ten years on the vendor directory, eight months on the setup page. This course is not going to pick a winner, because neither page is the vendor. The directory page carries its own warning — it is labelled current as of 2 March 2023 and says that data are provided by third parties and that offerings change often. Treat every history-depth figure in AmiBroker’s documentation as a starting point for a question you put to the vendor, not as a fact about what you would receive today.

Tick data

A tick is a single reported event — a trade, or a change of bid or ask. Tick data is not a finer bar interval; it is the material bars are made from, and working with it changes what your database is.

Three constraints are documented and all three bite quickly.

Edition. Tick charts, tick backtesting and tick scanning, along with one-, five- and fifteen-second bars, are Professional-edition capabilities. The edition page footnotes tick support further: it is available only through eSignal real-time, Interactive Brokers, or a DDE feed.

Resolution you cannot buy back. Interactive Brokers’ finest backfill resolution is documented as one-second bars even when the database’s base interval is tick. Choosing a tick base interval does not conjure tick history out of a vendor that does not keep it.

Storage. One bar of data occupies 40 bytes per symbol, so 100,000 bars is about 4 MB per symbol actually allocated, and the performance chapter advises against exceeding 100,000 bars for that reason. The eSignal documentation describes tick and second periodicities as pulling several megabytes for a single symbol and very few days of history, and recommends one-second bars over pure ticks as the faster option. The IQFeed integration carries a hard ceiling of five million ticks or bars per symbol, imposed by the vendor’s own connection software.

✕Common mistake

Choosing tick as the base interval “to keep all the detail”, on the reasoning that you can always compress up later. Compressing up is free and decompressing down is impossible, so the reasoning is sound — but it silently commits you to Professional, to one of three sources, to a storage budget most learners have not estimated, and to whatever tick history the vendor actually retains, which for one documented source is 2,000 bars. Part 19 makes this decision properly.

Why it costs money: entitlements

Market data is licensed, and the licence chain mirrors the architecture from the previous lesson. A venue owns the prices formed on it and licenses their redistribution. A vendor pays for that licence, adds its own service, and re-licenses to you. Your subscription fee is therefore usually two fees stacked: the vendor’s charge for the service, and the venue’s charge for its data. AmiBroker’s IQFeed page states this directly in its price list — exchange fees are extra for real-time data, on top of the monthly service charge.

Entitlements have three practical consequences that surprise people.

They are per venue, not per vendor. A subscription that covers US equities does not cover US futures, options, or any other country, and each addition is separately priced. Your symbol may resolve, chart correctly, and simply never receive a quote.

They can be withdrawn, and your database notices. Norgate’s plugin documentation states that symbols are presented according to subscription entitlement, and that if a market subscription lapses those symbols are removed from the AmiBroker database the next time database maintenance runs. That is a data source deleting rows from your local database because a payment stopped.

Broker feeds have their own conditions. Interactive Brokers’ data is tied to that broker’s own market-data subscriptions, and the AmiBroker documentation notes that backfill does not work on demo accounts at all — a Trader Workstation limitation. The vendor directory’s note that IB data costs around ten dollars a month in commissions, or nothing if monthly commissions exceed thirty, comes from a page dated March 2023 and is exactly the sort of commercial term that changes.

⚠Warning

Every price in AmiBroker’s documentation, including the ones quoted above, is on a page that either dates itself or contradicts another AmiBroker page. Never commit money on the basis of a figure in a course, a manual, or a forum post. Get it from the vendor, in writing, for the specific venues you need, and confirm whether exchange fees are included.

The other meaning of “professional”

This is the sentence that saves people money: the word “professional” appears twice in this subject, and the two uses have nothing to do with each other.

AmiBroker Professional is an edition of a piece of software. You buy it once from AmiBroker, and the next lesson deals with what it adds.

Professional subscriber status is a market-data classification. Venues distinguish between subscribers who use data privately and those who use it in a business, regulated or advisory capacity, and they charge the second group considerably more — often several times more. The classification is made by each venue, applied by your vendor through the subscriber agreement you sign, and it is entirely independent of which AmiBroker edition you own.

AmiBroker’s documentation does not define this classification and cannot tell you which side of the line you are on. Nor can this course: the criteria differ by venue and by jurisdiction, and they turn on facts about you rather than about your software. What this course can tell you is that the question exists, that it is answered in your vendor’s subscriber agreement, and that answering it wrongly is a billing problem you find out about later.

What you can learn for nothing

A great deal, and it is worth being specific rather than encouraging.

End-of-day history is free and plentiful. AmiQuote — the downloader bundled with the AmiBroker installer, and licensed separately from AmiBroker itself, as Part 3 sets out — has documented built-in sources including Yahoo Finance historical data, Stooq, Tiingo and Quandl with API keys, and forex from FinAm, plus a user-definable data-source mechanism for any CSV-over-HTTP feed. The data those sources supply costs nothing. That covers essentially every research question in Parts 27 to 35, all of the charting and indicator work in Parts 4 to 7, and all of the scanning in Part 12.

Historical intraday is sometimes free, and the situation is unstable. One built-in AmiQuote source is documented as supplying intraday forex, and the shipped example data-source definitions include an intraday one. Whether any specific free intraday source works this month is precisely the kind of fact that changes: AmiQuote’s own release history records Yahoo’s historical download going defunct in one version and being reimplemented two versions later. Verify before you plan around it.

Bar Replay costs nothing and is genuinely different from reading a static chart. It plays historical data back at a chosen speed, for every symbol at once, and it affects formulas in charts and in Analysis alike. Part 26 uses it as the backbone of the practice exercises, and Parts 21 to 25 use it as the offline route through the live material.

▷Exercise

Level A path for this lesson. Nothing here needs a feed, but two checks make it concrete. First, open AmiQuote and look at its Source list: that list, on your machine today, is the real answer to what free data you have, and it is more current than any document. Second, take one symbol you already hold and write down which of the four products in the first table it is — the answer is almost certainly end-of-day history, and being able to say so precisely is the point. Keep that note; the next lesson asks you to turn it into an access level.

Recap

Four products hide behind the word “data”: end-of-day history, historical intraday, delayed current-session data and real-time streaming. Only the last is expensive, and it is expensive because venues license their own prices and vendors pass those licence fees on. Streaming and history are separate purchases, backfill depth varies by an order of magnitude between vendors, and AmiBroker’s own documentation contradicts itself about at least one vendor’s depth — which is a reason to ask the vendor, not a reason to distrust AmiBroker.

Tick data is not simply a smaller interval; it commits you to a Professional edition, a short list of sources, and a storage budget worth estimating in advance. And “professional” has a second meaning, set by venues rather than by software, that decides what your subscription costs.

The next lesson turns all of this into a decision: what AmiBroker itself requires, what the three access levels are, and exactly which parts of this course each one completes.

Check your understanding

Question 1. A vendor offers a "delayed" product. Which pair of questions actually determines whether it is useful to you?

• The price and the number of symbols
• The length of the delay, and whether the data streams or must be requested
• The exchange coverage and the payment method
• The delay length and the software version required

Show the answer and why

Answer: The length of the delay, and whether the data streams or must be requested

Delay length decides what the data can be used for; delivery shape decides whether a chart updates on its own. AmiBroker’s vendor directory labels one provider’s delayed product "DELAYED, not streaming" precisely because those are two independent properties. Symbol counts and pricing matter, but neither tells you what the product does.

Question 2. You subscribe to a real-time feed and configure a database with a tick base interval. Your intraday charts show only a few days of history. What is the most likely explanation?

• AmiBroker cannot store more than a few days of tick data
• The vendor’s tick backfill depth, or the Number of bars to load, or both, are smaller than you assumed
• The Professional edition is required to store tick data
• The plugin is disconnected

Show the answer and why

Answer: The vendor’s tick backfill depth, or the Number of bars to load, or both, are smaller than you assumed

Backfill depth is the vendor’s decision and varies enormously — one documented source supplies ten days of tick, another 2,000 bars at second intervals. Number of bars to load is yours, and caps what is kept regardless. The Professional edition is needed to use tick intervals at all, but that would prevent the chart existing, not shorten it.

Question 3. Which of these follow from the fact that market data is licensed by venues? Select all that apply.

• Your monthly cost may include venue fees on top of the vendor’s service fee
• Entitlements are granted per venue, so one symbol can stay blank while others update
• A lapsed subscription can cause symbols to disappear from your local database
• AmiBroker can grant you access to a venue you are not entitled to, using a plugin setting

Show the answer and why

Answer: Your monthly cost may include venue fees on top of the vendor’s service fee, Entitlements are granted per venue, so one symbol can stay blank while others update, A lapsed subscription can cause symbols to disappear from your local database

The first three are documented behaviours: exchange fees extra on the IQFeed price list, per-venue entitlements, and Norgate’s plugin removing unentitled symbols at database maintenance. The fourth is not a thing any software can do, and treating an entitlement problem as a configuration problem is the most common way to waste an afternoon.

Question 4. True or false: buying the AmiBroker Professional edition changes how much your data vendor charges you.

• True
• False

Show the answer and why

Answer: False

False. The AmiBroker edition is a software licence bought once from AmiBroker. What a vendor charges depends on the venues you are entitled to and on whether the venue classifies you as a professional subscriber — a status decided by the venue and recorded in your subscriber agreement, with no connection to which edition of which analysis package you run.

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