Bug in calendar data [Confirmed]

Dominik Egert 2026.04.25 10:54

Found an error in the data retrieved from API-Calendar functions:

//+------------------------------------------------------------------+
//| Script program start function                                    |
//+------------------------------------------------------------------+
void OnStart()
{
    MqlCalendarEvent events[1];
    MqlCalendarValue values[];    

    CalendarEventById(36030016, events[0]);
    CalendarValueHistoryByEvent(36030016, values, D'2024.01.01', D'2024.02.02');
    ArrayPrint(events);
    ArrayPrint(values);

    return;
}

Result:

2026.04.25 12:52:04.862 TestSessionTimes (ASX200,H4)            [id] [type] [sector] [frequency] [time_mode] [country_id] [unit] [importance] [multiplier] [digits]              [source_url]    [event_code]           [name] [reserved]
2026.04.25 12:52:04.862 TestSessionTimes (ASX200,H4)    [0] 36030016      2       12           0           1           36      0            0            0        0 "https://www.rba.gov.au/" "new-years-day" "New Year's Day"        ...
2026.04.25 12:52:04.862 TestSessionTimes (ASX200,H4)          [id] [event_id]              [time]            [period] [revision] [actual_value] [prev_value] [revised_prev_value] [forecast_value] [impact_type] [reserved]
2026.04.25 12:52:04.862 TestSessionTimes (ASX200,H4)    [0] 188355   36030016 2024.01.01 00:00:00 1970.01.01 00:00:00          0 -9223372036854 -92233720368 -9223372036854775808 -922337203685477             0        ...
2026.04.25 12:52:04.862 TestSessionTimes (ASX200,H4)    [1] 188356   36030016 2024.02.01 00:00:00 1970.01.01 00:00:00          0 -9223372036854 -92233720368 -9223372036854775808 -922337203685477             0        ...

Dominik Egert 2026.04.28 12:56 #1

More screwed data, and this is across the board of any holyday, the historic calendar data is simply completley useless. - Best calendar on the market.

Some countries dont celebrate Easter Monday consistently, do they?!

h_time                  country_name    id              type    sector  frequency       time_mode       country_id      unit    importance      multiplier      digits  source_url                              event_code          name                
2026-04-06 00:00:00         Australia       36030021    2           12      4           1               36              0           0           0               0           https://www.rba.gov.au/&nbsp;                easter-monday       Easter Monday   
2025-04-21 00:00:00         Australia       36030021    2           12      4           1               36              0           0           0               0           https://www.rba.gov.au/&nbsp;                easter-monday       Easter Monday   
2024-04-01 00:00:00         Australia       36030021    2           12      4           1               36              0           0           0               0           https://www.rba.gov.au/&nbsp;                easter-monday       Easter Monday   
2023-04-10 00:00:00         Australia       36030021    2           12      4           1               36              0           0           0               0           https://www.rba.gov.au/&nbsp;                easter-monday       Easter Monday   
2022-04-18 00:00:00         Australia       36030021    2           12      4           1               36              0           0           0               0           https://www.rba.gov.au/&nbsp;                easter-monday       Easter Monday   
2021-04-05 00:00:00         Australia       36030021    2           12      4           1               36              0           0           0               0           https://www.rba.gov.au/&nbsp;                easter-monday       Easter Monday   
2020-04-13 00:00:00         Australia       36030021    2           12      4           1               36              0           0           0               0           https://www.rba.gov.au/&nbsp;                easter-monday       Easter Monday   
2019-04-22 00:00:00         Australia       36030021    2           12      4           1               36              0           0           0               0           https://www.rba.gov.au/&nbsp;                easter-monday       Easter Monday   
2018-04-02 00:00:00         Australia       36030021    2           12      4           1               36              0           0           0               0           https://www.rba.gov.au/&nbsp;                easter-monday       Easter Monday   
2017-04-17 00:00:00         Australia       36030021    2           12      4           1               36              0           0           0               0           https://www.rba.gov.au/&nbsp;                easter-monday       Easter Monday   
2027-03-29 00:00:00         Canada              124050011       2           12      4           1               124             0           0           0               0           https://www.statutoryholidays.com   easter-monday   Easter Monday   
2026-04-06 00:00:00         Canada              124050011       2           12      4           1               124             0           0           0               0           https://www.statutoryholidays.com   easter-monday   Easter Monday   
2025-04-21 00:00:00         Canada              124050011       2           12      4           1               124             0           0           0               0           https://www.statutoryholidays.com   easter-monday   Easter Monday   
2024-04-01 00:00:00         Canada              124050011       2           12      4           1               124             0           0           0               0           https://www.statutoryholidays.com   easter-monday   Easter Monday   
2023-04-10 00:00:00         Canada              124050011       2           12      4           1               124             0           0           0               0           https://www.statutoryholidays.com   easter-monday   Easter Monday   
2022-04-18 00:00:00         Canada              124050011       2           12      4           1               124             0           0           0               0           https://www.statutoryholidays.com   easter-monday   Easter Monday   
2025-04-21 00:00:00         France              250060006       2           12      4           1               250             0           0           0               0           https://publicholidays.fr/          easter-monday   Easter Monday   
2023-04-10 00:00:00         France              250060006       2           12      4           1               250             0           0           0               0           https://publicholidays.fr/          easter-monday   Easter Monday   
2022-04-18 00:00:00         France              250060006       2           12      4           1               250             0           0           0               0           https://publicholidays.fr/          easter-monday   Easter Monday   
2021-04-05 00:00:00         France              250060006       2           12      4           1               250             0           0           0               0           https://publicholidays.fr/          easter-monday   Easter Monday   
2020-04-13 00:00:00         France              250060006       2           12      4           1               250             0           0           0               0           https://publicholidays.fr/          easter-monday   Easter Monday   
2019-04-22 00:00:00         France              250060006       2           12      4           1               250             0           0           0               0           https://publicholidays.fr/          easter-monday   Easter Monday   
2018-04-02 00:00:00         France              250060006       2           12      4           1               250             0           0           0               0           https://publicholidays.fr/          easter-monday   Easter Monday   
2025-04-21 00:00:00         Germany             276080006       2           12      4           1               276             0           0           0               0           https://publicholidays.de/          easter-monday   Easter Monday   
2023-04-10 00:00:00         Germany             276080006       2           12      4           1               276             0           0           0               0           https://publicholidays.de/          easter-monday   Easter Monday   
2022-04-18 00:00:00         Germany             276080006       2           12      4           1               276             0           0           0               0           https://publicholidays.de/          easter-monday   Easter Monday   
2021-04-05 00:00:00         Germany             276080006       2           12      4           1               276             0           0           0               0           https://publicholidays.de/          easter-monday   Easter Monday   
2020-04-13 00:00:00         Germany             276080006       2           12      4           1               276             0           0           0               0           https://publicholidays.de/          easter-monday   Easter Monday   
2019-04-22 00:00:00         Germany             276080006       2           12      4           1               276             0           0           0               0           https://publicholidays.de/          easter-monday   Easter Monday   
2018-04-02 00:00:00         Germany             276080006       2           12      4           1               276             0           0           0               0           https://publicholidays.de/          easter-monday   Easter Monday   
2025-04-21 00:00:00         Hong Kong       344030005   2           12      4           1               344             0           0           0               0           https://publicholidays.hk/          easter-monday   Easter Monday   
2023-04-10 00:00:00         Hong Kong       344030005   2           12      4           1               344             0           0           0               0           https://publicholidays.hk/          easter-monday   Easter Monday   
2022-04-18 00:00:00         Hong Kong       344030005   2           12      4           1               344             0           0           0               0           https://publicholidays.hk/          easter-monday   Easter Monday   
2021-04-06 00:00:00         Hong Kong       344030005   2           12      4           1               344             0           0           0               0           https://publicholidays.hk/          easter-monday   Easter Monday   
2021-04-05 00:00:00         Hong Kong       344030005   2           12      4           1               344             0           0           0               0           https://publicholidays.hk/          easter-monday   Easter Monday   
2020-04-13 00:00:00         Hong Kong       344030005   2           12      4           1               344             0           0           0               0           https://publicholidays.hk/          easter-monday   Easter Monday   
2019-04-22 00:00:00         Hong Kong       344030005   2           12      4           1               344             0           0           0               0           https://publicholidays.hk/          easter-monday   Easter Monday

Alexey Petrov 2026.04.28 13:41 #2

Dominik Egert #:
Some countries dont celebrate Easter Monday consistently, do they?!

Which ones exactly from your list? Any prooflinks please?

Alexey Petrov 2026.04.28 13:44 #3

Dominik Egert:
Result:

We have fixed an error related to this year's holiday events. Calendar will be updated soon.

Still checking the one related to NY in February (this what you mean I believe).

Dominik Egert 2026.04.29 06:56 #4

Alexey Petrov #:

We have fixed an error related to this year's holiday events. Calendar will be updated soon.

Still checking the one related to NY in February (this what you mean I believe).

Please look at the holidays I listed. Easter Monday is a holiday that takes place every year, but the list is missing multiple entries. The list is just an example, showing some of the missing entries.

New year also only takes place once a year, and for sure not on Feb, 1.

I would assume there are even more faulty and missing entries in the db. - Do I need to check them all for you?

There are multiple services available via API to get holiday data. Maybe you guys could cross-check your db with one of them.

It is clear there is a "mess" in the data when it comes to holidays. I didn't check the other events. Its to much for me alone to go through and verify each one.

But the errors in the holidays alone are diminishing my confidence in the data. - I guess someone needs to go through the data and make sure its reliable.

If you need an extract, I can share a .sqlite with what I got from the API.

how come a line PositionsTotal() Efficiency of indicators vs

Enrique Dangeroux 2026.04.29 07:47 #5

Dominik Egert #:

It is clear there is a "mess" in the data when it comes to holidays. I didn't check the other events. Its to much for me alone to go through and verify each one.

But the errors in the holidays alone are diminishing my confidence in the data. - I guess someone needs to go through the data and make sure its reliable.

Forum on trading, automated trading systems and testing trading strategies

Libraries: Calendar

fxsaber, 2023.09.21 09:37

On the relevance of calendar data.

For comparison the work of another source.

It regurlarly happens it takes hours for the actual data to show up.

Forum on trading, automated trading systems and testing trading strategies

Libraries: Calendar

fxsaber, 2024.03.21 09:49

Unfortunately, you can't trust the current Calendar.

Here is the omission of an important CHF news in the list of events and the corresponding market reaction to it.

And this is another calendar, where the news is present.

Important events totally absent.

Unfortunately the Mql5 calander is a liability instead of an asset.

By the way, it has been for years.

Discussing the article: "Using Libraries: Calendar MT5 Calendar library can't

Dominik Egert 2026.04.29 13:48 #6

Enrique Dangeroux #:

It regurlarly happens it takes hours for the actual data to show up.

Important events totally absent.

Unfortunately the Mql5 calander is a liability instead of an asset.

By the way, it has been for years.

I gave up on that a few years ago, but holidays... That should be something you can't screw up that hard, even if I tried.

I think, (and have done so) it is possible to implement working versions of the Calendar functions. Working referring to: consistent and accurate data.

Object-Oriented Programming - Overload Tracking event changes by OOP fundamentals: Abstraction

democog 2026.04.29 14:29 #7

Hello,

IMO guys you are a bit too harsh, the calendar offered here, with API as well, is a bless; a ready made solution, for free.. what's more to ask? Also, there are more ways to look for "abnormal" market behavior - besides going for a super expensive API offer from some company..

For a somehow hilarious moment, you can also have a look at this post :)

https://www.mql5.com/en/forum/484132/page15#comment_58685516

greets

Libraries: Calendar

2025.10.08
www.mql5.com

Articles, Library comments: Libraries: Calendar

Creating Expert Advisors in MetaTrader 5 for a MetaTrader 5 for hedge

Enrique Dangeroux 2026.04.29 15:06 #8

Dominik Egert #:
Working referring to: consistent and accurate data.

Yes. So the data is inconsistant and not accurate. How does that translate to a "working" version?

democog #:

Hello,

IMO you guys are a bit too harsh, the calendar offered here, with API as well, is a bless; a ready made solution, for free.. what's more to ask? Also, there are more ways to look for "abnormal" market behavior - besides going for a super expensive API offer from some company..

For a somehow hilarious moment, you can also have a look at this post :)

https://www.mql5.com/en/forum/484132/page15#comment_58685516

greets

The Library is great. All Sabers libs are. The hilarity will vanish if you rely on the mql5 calendar when you think you have filtered out important events, when an important event is not considered and you lsoe money because of it.

Forex Factory calendar is also free and the consistancy and quality is far beyond that of the Mql5 version.

Tracking event changes by SQLite database Economic calendar

democog 2026.04.29 15:22 #9

Enrique Dangeroux #:
The Library is great. All Sabers libs are. The hilarity will vanish if you rely on the mql5 calendar when you think you have filtered out important events, when an important event is not considered and you lsoe money because of it.

Forex Factory calendar is also free and the consistancy and quality is far beyond that of the Mql5 version.

When referring to the Calendar API, I am referring to the official MQL API, which for me is enough I may say.. Regarding the comment I referred, we can see that the market reacts to ..both calendars, which is quite a hilarious moment for that matter :) But anyway, as I said, calendars are the one part of the equation, what you would do if there is a sudden, non listed event happening? We saw plenty of those recently, as well, so there should be more ways to look for problems anyway

greets

Tracking event changes by Economic calendar Functions

Dominik Egert 2026.04.29 16:31 #10

democog #:

greets

Example:

Upcoming holiday on calendar. Is it traded or not? How to check: find holiday in last year, try to get data for that holiday. Data there? Now you know.

Imagine new year on Feb. 1. Data there! Trading day.

Do you see the problem?

And this is just the holidays. I understand the update delay compared to other sources, but holidays should be reliable.

And if these entries are not of quality, what's going to be the outlook on dynamic data and events.

The current calendar is insufficiently maintained, but advertised as its own product, called Tradays.

Since I've been calling this out for years, with others here on the forum, it is no wonder, I am annoyed.

I still report bugs, and still I dont see them being recognized, over and over. Yeah, I am calling it out, and I start with an objective post, with every repetition, my frustration levels up and gets reflected in the wording.

I called out _StopFlag bug in January, now, after another user has reported, I added in again, and it got taken to the devs. - Yes, this is annoying.

Tracking event changes by Chart change event How to Purchase an

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