Strategic significance in the statutory biodiversity metric: where the multiplier is chosen, which cells apply it, and what the workbook does not check

Strategic significance is one of the four things that make a habitat parcel worth more or fewer units in the statutory biodiversity metric: area, distinctiveness, condition and this. The user guide says how to assign it, and GOV.UK is the place to read that guidance. This page is about what the calculation tool does with the choice: which column takes it on each sheet, the lookup table the multiplier comes from, the formulas that apply it, the strings the cells write when the lookup fails, and what the free Quadrat check does and does not say about it. Every statement below was read from the formulas of the published workbooks named under Sources.

“Strategic significance is the local significance of the habitat based on its location and habitat type.” — statutory biodiversity metric user guide, June 2026, p. 29

Three categories, one lookup table

In the statutory metric 1.0.4 the choice is a drop-down whose list is three cells on the hidden lookup sheet G-3 Multipliers, L4 to L6. The category name and the multiplier sit beside each one, in columns M and N:

The watercourse sheets read the same three rows from their own data sheet, G-7 WaterC' Data, AK4 to AM6, with the same values. The drop-down refuses a typed value that is not one of the three (the validation shows an error message); a pasted value is not refused, which matters below.

The small sites metric 1.2.3 has two categories, not three. Its list is 11. Lists F36 to F37 — Formally identified in local strategy at 1.15 and Area/compensation not in local strategy/ no local strategy at 1 — and the medium category does not exist in that workbook.

Which column takes the choice, and which cells apply it

Every data-entry sheet of the statutory metric has the same three-column pattern: the cell you choose in, a hidden cell beside it that looks up the category name, and a hidden cell that looks up the multiplier. The user guide's data-entry appendix lists the field once for all sheets: “Strategic significance — Dropdown list — All sheets” (p. 83).

Columns as in metric 1.0.4; the first parcel row is 11 on the area baseline and creation sheets, 12 on the area enhancement sheets, 10 on the hedgerow and watercourse baseline sheets, 12 on their creation and enhancement sheets. The category and multiplier columns are hidden by the sheet's buttons.

The unit formulas that apply it

• Baseline (A-1, Q): Total habitat units = area × distinctiveness score × condition score × strategic significance multiplier (H × J × L × O). Baseline units retained and Baseline units enhanced (U, V) use the same four factors over the retained and enhanced areas.
• Creation (A-2, Y): Habitat units delivered = area × distinctiveness score × condition score × strategic significance multiplier × final time-to-target multiplier × difficulty multiplier (G × I × K × N × T × X).
• Enhancement (A-3, AN): the gain between the baseline and the proposed scores is discounted by the time-to-target and difficulty multipliers, the baseline value is added back, and the whole figure is multiplied by the proposed parcel's strategic significance multiplier (AC). The baseline parcel's own category and score, shown in L and M, are copied from A-1 for reference; the units-delivered formula does not read them.
• Small sites metric (5. Area Habitats, L): Total habitat units onsite = (area in m² ÷ 10,000) × distinctiveness score × condition score × strategic significance multiplier (AD, looked up from 11. Lists). The enhancement block's L column applies its multiplier (AP) the same way the statutory metric's AN does.

The strings a wrong or missing choice produces

Spatial Data Missing

Every category and multiplier cell has the same guard: if the lookup returns zero, write Spatial Data Missing, with a ▲ on A-1's multiplier cell, a ⚠ on every other sheet's, and no symbol at all on the category cells of A-1 and B-1 and on both of A-2's cells. In the published 1.0.4 the three multipliers are 1.15, 1.1 and 1 and the lookup range (L3 to N6) has no empty multiplier cell, so a choice from the drop-down cannot produce the string; it is a guard against a lookup resolving to an empty cell. A value that is not in the list at all — pasted in, or carried over from another file — does something different: the exact-match lookup fails, the category and multiplier cells show #N/A, and what the row's unit cells then do depends on the sheet.

The same string is also written by cells that have nothing to do with strategic significance. On the off-site sheets the spatial risk category multiplier (D-1 S, D-2 Z, D-3 AO, E-1 P, F-1 T; lookup G-3 S3 to T10, or G-7 for watercourses) carries the identical guard, and so do the watercourse encroachment multipliers on C-1 and F-1 (N and P). It is the workbook's general “a location multiplier did not resolve” string, so read the column header before acting on it.

What happens when the cell is left blank

The drop-down allows a blank, and the workbook does not flag the blank itself (except on the hedgerow baseline sheets, where K writes Check data ⚠ as soon as a hedge type is entered without a category). A blank category gives a blank multiplier, and multiplying an area by a blank text cell is an Excel error, which each sheet handles differently:

• A-1: Total habitat units (Q) and Units lost (X) wrap the arithmetic in an error catch and write Check Data ▲. The row is visibly flagged. D-1 does the same in Total habitat units (T) and writes Check Data ⚠ in Total habitat units (SRM) (Q) and Units lost (AA).
• A-2 and A-3: Habitat units delivered (Y on creation, AN on enhancement) catches the error and writes an empty cell. The row scores nothing and raises nothing: a parcel with an area, a habitat and a condition contributes zero units with no ▲ or ⚠ anywhere on its row. (The off-site D-2 and D-3 unit cells were not read for this page; their lookup cells were, and match A-2's and A-3's.)
• Small sites metric, 5. Area Habitats: Total habitat units onsite (L) writes Error ▲; if the row also has an Area Lost, Units lost (N) writes This intervention is not permitted within the SSM ▲, which is that cell's catch-all for any arithmetic error and says nothing about the cause.

What clears all of it: choose one of the listed categories from the drop-down on every row that has an area or a length, so the cell holds the listed string exactly. Nothing else in the row is read by these lookups.

What the workbook does not check

The workbook applies whichever of the three categories the row holds. It has no test for the rules the user guide sets on when a category may be used:

• “Once an LNRS has been published, the baseline strategic significance values for habitat parcels in that area should always be scored as low.” (p. 29) The baseline sheets accept high and medium without comment.
• Where a Local Nature Recovery Strategy has been published, the medium category “cannot be applied” to post-development interventions (Table 7, p. 30). The creation and enhancement sheets accept it.
• Where no LNRS is published and the planning authority has specified alternative documents, a high category needs the plan named: “You should record the name of the plan the relevant planning authority has specified in the user comments” (Table 8, p. 32). No cell reads the User comments column.

Nothing on Headline Results or Detailed Results mentions strategic significance; the multiplier is already inside every unit figure by the time those sheets read them. So the category on each row is a claim the reviewer checks against the LNRS or the specified documents, and the workbook is silent on it.

What the free check does with it

Drop the metric on the check page and Quadrat reads every data-entry sheet. The strings above that carry a symbol — Spatial Data Missing ⚠, Check Data ▲, Check data ⚠, Error ▲ — are listed by sheet and cell with the parcel's reference, habitat and User comments beside them; any ▲ makes the verdict Not ready. The cells that write the string without a symbol (the category cells of A-1 and B-1, A-2's pair) are not listed, and an #N/A on a data-entry sheet is not listed either: it is a spreadsheet error, not a flag string. A blank category on a creation or enhancement row is therefore invisible to the check, as it is to the workbook.

One question the check asks that the workbook does not: for every parcel whose strategic significance reads Formally identified in local strategy and whose User comments cell is empty, it lists an evidence gap — the high multiplier only applies where the location is formally identified in a local strategy, and the guide asks for the document to be named in the comments. Quadrat does not judge whether the category is right, does not read an LNRS, and never recalculates a unit; it copies the workbook's stored values.

Sources

The statutory biodiversity metric calculation tool 1.0.4 (macro-disabled workbook) and the small sites metric 1.2.3, both as published on GOV.UK's Statutory biodiversity metric tools and guides page and read on 3 October 2026: the columns, cells, lookup ranges and formulas named above are theirs, and the category names are quoted from G-3 and 11. Lists as written. The statutory biodiversity metric user guide, June 2026 edition, pp. 29–32 (strategic significance, Tables 7 and 8), p. 83 (the data-entry appendix) and p. 87 (combining parcels of the same strategic significance). A later release of either workbook may move a cell or change a string; the version each statement rests on is named here so it can be checked. Quadrat is not affiliated with Defra or Natural England. If a cell on this page does not match the workbook in front of you, write to hello@quadrat.uk; replies are signed as Quadrat.