diff --git a/audit/var-138.md b/audit/var-138.md
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+# Chain Variable Transaction 138
+
+## Changes
+
+This transaction changes `poc_challenge_rate` from `300` to `250`.
+
+## Version threshold
+
+None
+
+## Transaction
+
+````
+[{1363174,
+  [{blockchain_txn_vars_v1_pb,[{blockchain_var_v1_pb,"poc_challenge_rate",
+                                                     "int",<<"250">>}],
+                              0,
+                              <<48,69,2,32,96,184,144,10,210,29,173,76,35,149,43,233,
+                                161,84,126,140,49,...>>,
+                              <<>>,<<>>,[],[],138,[],[],[]}]}]```
+
+## Acceptance block
+
+1363174
+
+## Acceptance block time
+
+2022-05-21 05:13:29 UTC
+````