Contracts

The Net Magic Number — a measure of how much new ARR each S&M dollar generates after accounting for churn — has been flat at 0.50 for four consecutive years. That stability is not stability in the encouraging sense: it means the churn tax consuming roughly a fifth of gross sales efficiency has become structural, not cyclical, and contract structure is the biggest lever still available to move it.

The Net Magic Number

The Net Magic Number is the Gross Magic Number (new ARR per S&M dollar, before churn) minus the Churn Tax (the share of that efficiency consumed by lost revenue in the same period). Where Gross Magic Number has moved modestly year to year — 0.64 (2022) → 0.65 (2023) → 0.64 (2024) → 0.66 (2025) — Net Magic Number has not moved at all: 0.50 in every one of those years.

Read against the chart: Gross Magic Number, Net Magic Number, and Churn Tax as a share of gross efficiency (the line, right axis) — a Churn Tax that has sat at 0.14–0.16 for four years while Gross Magic Number recovered slightly is the signal that churn is absorbing a growing share of whatever sales-efficiency gains the business makes.

The Churn Tax

A flat Net Magic Number at 0.50 for four straight years, against a Gross Magic Number that has wobbled but not meaningfully improved, means the churn tax is not a cyclical drag that recovers with the market — it is a fixed cost of doing business in this segment, roughly 22–24% of gross sales efficiency in every year measured.

This connects directly to the contract-length dynamics documented under Churn: the strongest lever against churn — multi-year contracts — is the one companies are abandoning fastest, which means the churn tax has no obvious mechanism to improve without a deliberate reversal of that trend.

The Contract Mix Shift

Multi-year contract adoption fell from 48% to 26% of new agreements in a single year, with annual contracts absorbing most of the shift (39% → 52%) and monthly picking up the rest (13% → 22%). Given that multi-year contracts cut churn by roughly 70% versus monthly, this compositional shift is itself a direct input into why the churn tax hasn't moved.

There is a second, quieter effect: professional-services investment as a share of ARR has an optimal zone — roughly 5–15% of ARR — that correlates with the lowest churn (~5%). Both under-investment (<5% of ARR, 18% churn) and over-investment (>15% of ARR, 12% churn) correlate with worse outcomes. Contract structure and services investment together account for most of the variance in churn tax across companies in the survey, more than product differences do.

The path to moving the Net Magic Number off 0.50 runs through contract terms first: defending multi-year commitments in negotiation, calibrating PS investment to the optimal band, and pricing the term differential clearly enough that buyers see the tradeoff — not through S&M spend reduction alone, which is the OpEx-side lever addressed separately.