Rule of 40

The level of revenue at which total costs equal total income, resulting in neither profit nor loss. For growth businesses, understanding break-even informs decisions about pricing, unit economics, and the capital required to reach profitability.

The set of key performance indicators specifically designed to measure the health, growth, and unit economics of Software-as-a-Service businesses. Core SaaS metrics include annual recurring revenue (ARR), monthly recurring revenue (MRR), customer acquisition cost (CAC), lifetime value (LTV), churn rate, net revenue retention (NRR), and the Rule of 40.

EBITDA expressed as a percentage of revenue, indicating how much operating profit a company generates from each pound of revenue before non-cash charges and financing costs. EBITDA margin is a key benchmark for operational efficiency across industries.

A measure of a company's financial performance that calculates the value created above the required return of investors, defined as net operating profit after tax minus the cost of capital employed. EVA highlights whether a firm's intangible and tangible assets are generating returns that exceed their cost of capital.

Income received by a company for goods or services that have not yet been delivered or performed, recorded as a liability on the balance sheet. In SaaS and subscription businesses, deferred revenue is a key indicator of future recognised revenue and contract backlog strength.

The annualised value of recurring subscription revenue. ARR is the primary top-line metric for SaaS and subscription businesses, providing a normalised view of predictable revenue that strips out one-time fees and variable charges.

A software distribution model in which applications are hosted by a service provider and made available to customers over the internet on a subscription basis. SaaS businesses are characterised by recurring revenue, high gross margins, and significant intangible asset value in software and customer relationships.

A valuation ratio comparing a company's enterprise value to its annual revenue. EV/Revenue is often used to value high-growth or pre-profit companies where earnings-based multiples are not meaningful.

What is the Rule of 40?

The Rule of 40 states that a company's growth rate plus profit margin should total 40% or more — companies scoring below 40% risk unsustainable unit economics or insufficient growth.