diff --git a/docs/ARCHITECTURE.md b/docs/ARCHITECTURE.md
index 23ae57c..3219b69 100644
--- a/docs/ARCHITECTURE.md
+++ b/docs/ARCHITECTURE.md
@@ -61,10 +61,11 @@ history from the full DataFrame and supplementary data from marts. Comparisons
 batch supplementary queries across selected URNs. Async routes still contain
 synchronous dependency calls; a fully asynchronous database layer is not present.
 
-Benchmarks are DfE's own figures, read from marts: `fact_ks2_national_averages`
-and `fact_ks4_national_averages` for England, and `fact_ks4_la_averages` (all
-state-funded schools) for the search rows' "vs LA avg". The API never averages
-school rows to make a benchmark.
+DfE's official benchmarks live in marts: `fact_ks2_national_averages` and
+`fact_ks4_national_averages` for England, and `fact_ks4_la_averages` (all
+state-funded schools, per LA) for the search rows' "vs LA avg".
+`data_loader.compute_benchmarks` computes further state-school benchmarks from
+our own dataset; they are not DfE figures and are labelled as computed.
 
 ## Frontend boundaries