> ## Documentation Index > Fetch the complete documentation index at: https://docs.beaconrevenue.io/llms.txt > Use this file to discover all available pages before exploring further. # Segment net revenue retention > How much revenue the average account in a segment brings in at each month of its life, against its first month — a ratio, a curve rather than one number, and why it is not your company's net revenue retention. ## What it is `segment_net_revenue_retention` is how much revenue the average account in a segment brings in at a given month of its life, set against what the same accounts brought in in their first month. **It is not one number for a segment.** A segment carries a value for every month of an account's life, from month 1 to month 36, and the line those values make is what the figure exists to show: whether the typical account in that segment grows, holds or shrinks as it ages. It is a **ratio, not a percentage**: 1.32, not 132. At month 1 it is always 1.0. Above 1.0, the average account brings in more than it did when it started — the segment's accounts that grew outweigh the ones that shrank or left. Below 1.0, the segment loses more than it gains. **Accounts are lined up by their own first month, not by the calendar.** An account that started in March 2021 and one that started in June 2024 are both at month 1 in their first paying month. That is what lets one line describe a whole segment, however its customers arrived. ## How it is calculated Measured. It comes out of Beacon's calculation layer, where the rules are fixed and written down, and the same billing always produces the same line. [Definitions](/definitions/overview) sets out what the three method words mean. ```text theme={null} segment_net_revenue_retention at month m = revenue in month m of every account in the segment that has reached month m / revenue in month 1 of the same accounts ``` | Rule | What it means | | - | - | | First month | The first month an account paid you anything. That is its month 1 | | Revenue in a month | The account's recurring revenue across all its subscriptions that month | | Accounts that left | Count as zero — they stay in the line and stop adding revenue to it | | Accounts that came back | Count at what they pay again, from the month they return | | Closed months only | The current month is left out until it ends | | Who is counted at month m | Only accounts that have reached month m. A segment's line covers fewer accounts the further it goes, and stops at the age of its oldest accounts | | Which segment | The account's current confirmed segment. An account in no confirmed segment is not counted | Because the top and bottom are both sums of revenue, larger accounts weigh more than smaller ones. The figure describes the segment's revenue, not the typical account's experience — a segment can read above 1.0 while most of its accounts shrank, if a few large ones grew a great deal. ## Where it comes from Billing, through your confirmed segments. Billing is the required connection: with no billing there is no revenue on any account, so there is no line to draw. Segments is the second requirement — until your segment approver confirms at least one segment, there is nothing to draw a line for. It belongs to the Segments module, because it describes how a segment performs, and it is drawn on the [Segment revenue paths](/modules/segment-revenue-paths) page. Identity resolution matters here. Where two records for one business are not matched to each other, one of them stopping reads as an account that left, and the other starting reads as a new account at month 1. | Where it is available | | | - | - | | Read interface | Yes, with an opt-in | | MCP | Yes, with an opt-in | | Events | Yes, with an opt-in | | CRM property | Yes, with an opt-in | No read interface or MCP tool serves this value yet — the table above publishes the shape ahead of the doors. **Where the choice is made.** This value is not open by default on any door. The choice happens when a reader grant that reaches it is issued or widened, when you subscribe to events, or when you turn the CRM property on. Whoever makes it is shown who becomes able to see the value, and their yes is recorded — holding a grant is no longer enough on its own. That is a rule about where the value may travel, not about who inside your company may look at it. ## How fresh it is Worked out every night, after your billing loads, over every closed month. A new month joins the line the night after it ends. Unlike a cohort's curve, a point on this line can move after it is first drawn. Each night the line is redrawn over the accounts that have reached each month by then, so as younger accounts reach month 12, month 12 is struck again over a larger group. An account moving to another segment also takes its whole history with it. ## Currency and rounding No currency. It is a ratio of two revenue figures, both in your single reporting currency under the rules set out in [currency](/currency), and the currency cancels in the division. **No rounding rule is set for this value.** Today Beacon holds it to three decimal places — 1.325 — and whether that stays is not yet settled. A screen or an export may round it further for display — the page shows it as ×1.32 — so where you compare two points, compare them at the precision you received them. **And it is a ratio.** 1.32 means the average account brings in 32% more than in its first month. A reader expecting 132 and receiving 1.32 has the same figure. ## What changes it Accounts in the segment paying more, paying less, leaving or coming back. Accounts reaching a new month of their life, which adds them to that month's point. Your segment approver confirming, merging or splitting segments, which changes who is in each line. A resolved identity, which can turn an apparent departure and a new start into one continuing account. ## What it is not * **Not a percentage.** 1.32, never 132. * **Not one number for the segment.** It is a value per month of an account's life, and the line is the figure. * Not [`net_revenue_retention`](/definitions/net-revenue-retention). That reads your whole customer base over a calendar period and leaves out new and returning customers; this follows a segment's accounts by their own age and counts a returning account again. * Not [`cohort_net_revenue_retention`](/definitions/cohort-net-revenue-retention). That follows one group of accounts that started together, frozen at the start; this pools every account in a segment whatever month it started, lined up by age. * Not [segment logo retention](/definitions/segment-logo-retention). That counts accounts still paying; this weighs revenue, and the two part ways whenever the accounts that left were larger or smaller than the rest. * Not a forecast. Every point is billing history. Where a segment's accounts are younger than 36 months, the line simply stops. This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.