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$M and $MM

$M and $MM

$M and $MM

In all of the companies I've worked, I see the 'thousands' abbreviated as M and Millions as MM when presenting money (dollars typically) as in the following:

$ 125,000 would be $125M
$1,125,000 would be $1.25MM

Is this a hold-over from Roman numerals?  Why not use K for thousands and M for millions?  


This is normally the space where people post something insightful.

RE: $M and $MM

isn't that awfully confusing ?  but then if "all the companies I've worked" did it, it'd be a common practice; and the more "sensible" K and M would "confusiong" ...

i think ?

RE: $M and $MM

It's done both ways with tank capacities also, and is equally confusing.

RE: $M and $MM

Accoutants are not Engineers and vice versa.  This may be a better question for asking on an accounting forum because this is their milleu and we should probably be conforming to their standards if those standards are unambiguous.  I also think this could be very regional.  I bet accountants would be unhappy with $1.25 X 10^6, but it makes perfect sence to me.


Kirby Wilkerson

Remember, first define the problem, then solve it.

RE: $M and $MM

It is more industry-specific than regional.  I've seen MSCF mean "thousands of cubic feet at standard conditions" used in natural gas production all over the world (even people who regularly use metric volumes can tell you how many "M scuffs" they made, not sure why people outside the U.S. almost always replace "SCF" with "scuff" but they seem to).

The Roman Numerals "M" and by extension "MM" tend (in this industry) to be used more with volumes than with money.  If you said "kSCF" or "kbbl" you wouldn't have much communication (and you would really have a problem with "MSCF" being "mega ft^3 at standard conditions").  

On the other hand I often see "$123k" or "$123m" used as thousands and millions respectively.  Every now and then I see $123M, but that seems really ambiguous to me (I know that the standard symbol for 10^6 is M for mega, but people who use Roman numerals would be pretty sure it was 10^3).

It is unfortunate that "million" starts with a symbol that looks like the Roman Numeral for 1,000, but that is just the way it is.


RE: $M and $MM

and here.  $M means millions at this place.

RE: $M and $MM

How do you spell "Tower of Babel"?  The problem with the way these prefix/sufix are used is that EVERYONE who uses them is certain that he is using them correctly.  Also, EVERYONE reading the document is certain that he completely understands.  Frequently they're both wrong.


RE: $M and $MM

Well, as long as their is a glossary/key or similar in the document where the terms are explained, they are arguably used correctly.

It's when they aren't defined and people are relying on what they think is a convention that problems occur.

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What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?

RE: $M and $MM

I live a long way from the US and have never seen MM for million.

Anyway doesn't MM mean 2000 in roman numerals?
Perhaps MM denotes M x M in this case.

RE: $M and $MM

You are exactly right on both counts.  In Roman Numerals "MM" is "2000".  In oil field speak "MM" is "M x M" or one million.  The earliest reference I've been able to find to "MM" was in the 1930's and it doesn't matter if everyone in the industry realized how very wrong it is, it isn't going away.

I've seen MM=10^6 used in the Oil & Gas industry all over the world, the first time I saw MMm3 (meaning millions of cubic meters) I laughed.  I saw a Canadian annual report last year where a company stated their volumes as "MME3m3" meaning "millions of cubic meters at standard conditions times 10^3".  Canada is the only place that I see E3m3 which means k(Nm^3), but is a bit "clearer" than km3 which would probably be taken as cubic kilometers.


RE: $M and $MM

I have seen this regularly in US multinationals referring money and volumes.  Also MBH thousands of btu per hour from utility gas.  MMGPY showed up in ethanol production.  An American thing.  My american wife uses this notation.

RE: $M and $MM

All the confusion stems from the Latin word for 1000, mille. Useful for counting 1000s of years (millennia) and evidently lots of other stuff. Shows up twice in the unit MCM (thousands of circular mils (mils are thousandths of an inch)). Probably also the source of the Roman numeral M. Interesting that the SI prefix m for mili is 1/1000, but M is not the counterpart for 1000. MCM is being dropped in favor of kcmil. I guess if the USA doesn't go entirely metric, we'll just gradually start borrowing some of the prefixes.   

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