What are the correct calculations for Romi and Roas?

Question

Analytics

Hello. Situation: we have several traffic sources - context (Yandex, Google, Rsya/kms, video, etc.), social networks by analogy, etc. The report table lists all these sources with a division into types (google seo, seo Yandex, rsya, kms, video, search, etc.). We do traffic analytics.

Next, you need to calculate Roas, Romi and Roi.

Is it correct to count Romi and Roi only in terms of general indicators, and break Roas into the types of traffic sources written above?

Since Roas is purely revenue: advertising expense. Then we can get revenue and expenses for ryan, kms, video advertising, targeting, etc. Each item separately.

But. Romi is not only an advertising expense, but also all the accompanying - marketing salary, discounts, gifts, the cost of goods. All these components cannot be divided into types in the table - kms, rsya, video, search, seo, etc. Since, for example, taking into account the RFP of marketing on ryan, kms, search advertising, video, SEO, etc. will not work. It will be shared. Subtract, for example, 50k RFP from the revenue for rye, and then 50k RFP from the revenue for kms, etc., then you will get the curves.

So. Is it correct to count Romi as common without sharing as Roas?

We take the total revenue from all advertising sources and the total expense for them, taking into account discounts, gifts, cost, salary. And in the end, we think so Romi. Same for Roi.

Is this structure correct?

Answer 1

ROAS - it is better to consider only the "costs" of advertising and the revenue that can be attributed to this advertising.
ROMI is better to consider all "investments" in marketing, including research, development, production (advertising, signs, souvenirs) and placement and operating income from sales that can be attributed to this "investment" in THIS marketing.
Spreading "costs" and "investments" across channels or products is a separate exercise. If it is impossible to mechanically attribute a separate expense item to a particular communication channel (type of advertising) or product, then I advise you to distribute such items by the number of transactions or clients (not registrations and applications, but payments). For example, a chief accountant's remuneration of 20% will be attributed to the "Search" acquisition channel, since it generated 50% of sales from new customers for the period, and the share of sales from new customers is 40%.
When calculating all indicators (ROI to a lesser extent), it is important how the period is determined.
Networks and platforms usually offer to count the placement period and something after.
Everyone else doesn’t care, but there are subsequent sales to previously attracted customers and this is already LTV. For simplicity, you can ignore this or come up with (and agree with everyone) some kind of coefficient for each new client, for example, 2.5X to the revenue from the first transaction.