Its was just easier to take it as a % of rev for modeling purposes specially now that it has decreased to a more reasonable and assumed to be stable % of current revenue base.
Ideally if I were to do as proper model of 3Pea I would segment out each portion of the SG&A and apply different growth rates. But, for the most part it does have a certain correlation to revenue growth as we would assume that the "Selling" would go up as revenue increases due to increased incentive payouts to sales staff and that the general admin would likely not go up as much as revenue but would still increase slightly as you have more people serving/maintaining the growth in infrastructure and increased clients.
So in short I do not expect SG&A to grow as fast as revenue but it should still increase if they expect to aggressively ramp up.
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