User:Baron of Bastanchury
Banknote denomination code
A 20 ice mark note issued by the Central Bank of Westarctica has a number of security features and each note has a unique serial number printed on its front in two places. This serial number unique identifier, which is composed of for elements which are separated by hyphens. The first number is a four-digit number that indicates the denomination of the note. All four spaces in this number must be occupied: the value itself will be right-aligned, and any unused spaces are filled with the number zero. Thus, a 20 ice mark note always has a serial number that begins with 0020.
Note serial number
Next comes a set of alphanumeric codes corresponding to that bill’s unique serial number within its denomination series year and issue year, and is separated from the next two elements by a hyphen (-). It always contains eight numerical digits, and may or may not be followed by a letter.
Possible note serial letter code
If any two notes end up for any reason carrying the same note serial number, then this set of numbers will be immediately followed by a letter indicating the note belongs to a different set of series numbers; since note series numbers are not issued sequentially and do not correspond to any "order of printing" of such notes, the number of possible series numbers does not need to be exhausted in order for a serial number letter code to be needed on a note.
Serial year codes
Following the second block number is one (or more than one) digit corresponding to the serial year that the bill was first issued (though not the calendar number of that year itself)— for example, the first 20 ice mark note issued in 2019 (the first series year for the 20 ice mark note) will have an Arabic numeral 1 here, as will all other 20 ice mark notes issued in 2020, 2021, 2022, etc. However, if a new distinct series is created in any subsequent year (which could be 2019, 2020, 2030, or any year number), then that series will be coded with the next higher number in the sequence (i.e., 2, 3, etc.). There is no upper limit to this number. All bills within a given serial year will have the same basic visual format (arrangement of elements, use of colors and emblems) as other notes of that serial year, regardless of when that note was actually printed. If there is a major revision of a bill at a later date, this will invoke a new serial year code rather than simply a new series code (see below). The serial year code will always be followed by a hyphen.
Following the serial year is a final letter block indicating the note’s series code for that series year. This letter (or, potentially, letters, typically A-Z) corresponds to a minor variation for that note within its series year, and may be arbitrarily and non-sequentially chosen within the 26-letter Roman alphabet. All notes that follow the format and appearance of the original series year will have the same letter code(s) in this field; if the Bank of Westarctica decides to issue a different kind of note within the same series year, then that note will bear a different letter(s) here. Only if more than 26 such series letters become necessary for a given series year will the field contain two letters (e.g., “FR” or “AG” or any other two-letter code). There is no upper limit to the length of the series code which a note may bear, so long as each series note is identical in all aspects of its appearance (other than its serial number) to other notes in the same series year and can be clearly differentiated from other notes in different series. The series code does not indicate the note’s series year or printing year, though certain series years will only bear certain series codes (which means a series year may sometimes be deduced backwards from an apparent series code). All bills must have a series code, even if the appearance of that note never varies (in which case all such notes issued for that series year would have the same single- or double-letter series code letter).
A bill whose QR code reveals its serial number to be 0020-34992322C-4-Y indicates that this is a 20 ice mark note, note number 34992322, which, by virtue of the letter “C” at the end, means this note happens to be one of at least two notes with this particular serial number that was issued within some serial year, here indicated by the number 4 (the fourth serial year for the 20 ice mark note, the fourth time this note has seen a major new design— let us say that the Bank of Westarctica decided to issue newly designed 20-ice-mark notes in 2018, 2020, 2023, 2030. Then the 20-ice mark note which was largely redesigned in 2030 would be coded with the number 4, followed by ss series letter, in this case “E”, which only means that thisnote is somehow different from any other bill bearing the letter “A” or “H” or any other code in this field (but is not considered different enough to qualify for a different series number).
Another example: A note whose serial number is 12237770-1-3-AZ indicates that this note, number 12237770 (no other notes from this serial year or printing year bear this same serial number because there is no letter following the 0 at the end), matches the design of similar bills originally printed in that same series year (which, because it is a 1, must be 2018 but was actually printed in 2021 (the numeral 3 means that this bill was printed in 2018+3=2021, and that this note’s appearance is essentially the same as the 2018 note) and is the “AZ” series bill printed that year (meaning that there must have been at least 26 other series bills also printed that year for that series year, though this field does not tell the user additional information nor if more than 52 such series notes were eventually printed for that series year and print year).
Third example: A note with the code indicating 00030020A-2-4-WEX. This indicates that the note holds the serial number 00030030 and was the second note to bear that serial number for series year (because the first note with that number did not have the letter A at the end) and was printed in the style of the 2018 note plus... ...Two years, =2020, meaning this note was the for the issue year was 2020, and was... ...the 4th design for that bill that year of issue, and... ...belongs to the WEX series of bills issued that year and in the format of 2018 (?) Note (?)