
Ask HN: CMGR vs. straightforward percent growth - api
I have a question about growth as typically quoted for startup metrics.<p>Many guides I&#x27;ve seen quote a number called CMGR. An example is here:<p>http:&#x2F;&#x2F;a16z.com&#x2F;2015&#x2F;08&#x2F;21&#x2F;16-metrics&#x2F;<p>CMGR is apparently a bit of a standard, but it provides a number that&#x27;s in some cases significantly smaller than what you get if you do a straightforward percent growth calculation.<p>I understand the idea of dampening out variation but what if the variation is small? Why should the results be so hugely different? We&#x27;re talking 2X here.<p>I guess I&#x27;m looking for someone to go into the math behind the difference. Been a while since I&#x27;ve studied probability and stats, and the origin of the CMGR formula seems murky vs. other ways of computing this. I&#x27;m wondering if the CMGR formula carries assumptions that are not explained in any of the text I&#x27;ve found on it.
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MrQuincle
C stands for compound. It's just that you have to take the growth of January
into account for February.

