Base vs incremental
An MMM splits revenue into two kinds: base revenue, which would have arrived without any marketing this period, and incremental revenue, which each channel's spend caused. The split is the decomposition, and it is the single most consequential chart the model produces.
Base is not "organic" in the analytics-dashboard sense. Inside it live brand equity built by years of past marketing, distribution and shelf presence, pricing position, seasonality, word of mouth, and habitual repurchase.1 The base is what your company would earn this quarter if every campaign paused, which is precisely why boards find it fascinating and CMOs find it dangerous.
Dangerous because of a standard misreading: "the model says 60% of revenue is base, so marketing only drives 40%, so cut marketing." The base is high partly because past marketing built it, and it decays if unfed. This period's decomposition is a snapshot, not a counterfactual for a permanent shutdown. The honest use of a high base share is portfolio-level: it tells you how much of this quarter is momentum, and therefore how much of the growth plan must come from incremental channels.
The waterfall below is the shape to internalize; it recurs on every vendor deck you will ever see, and on every page of this site as its signature.
Illustrative model output, not benchmarks. Drag a channel above its 100% baseline and watch the segment flatten: that bend is a saturation curve, the reason doubling spend never doubles revenue.
Worked micro-example: a $10M quarter
Revenue $10.0M. Model decomposition: base $5.2M (52%), paid search $1.6M, paid social $1.4M, TV $1.2M, email $0.6M. Sanity check: the parts sum to the whole (5.2 + 1.6 + 1.4 + 1.2 + 0.6 = 10.0). If a vendor's decomposition does not sum, ask why before asking anything else. Figures are illustrative, not benchmarks.
Source ledger
Every numeric claim on this page resolves to one of these primary sources.
- [1]Wikipedia: Marketing mix modelinghttps://en.wikipedia.org/wiki/Marketing_mix_modelingretrieved 2026-08-02
- [2]Google Meridian documentationhttps://developers.google.com/meridianretrieved 2026-08-02