diff --git a/library/psa_crypto_slot_management.c b/library/psa_crypto_slot_management.c
index 3e18668..1d2e51f 100644
--- a/library/psa_crypto_slot_management.c
+++ b/library/psa_crypto_slot_management.c
@@ -438,9 +438,9 @@
     for( slot_idx = 0; slot_idx < PSA_KEY_SLOT_COUNT; slot_idx++ )
     {
         const psa_key_slot_t *slot = &global_data.key_slots[ slot_idx ];
-        if( ! psa_is_key_slot_locked( slot ) )
+        if( psa_is_key_slot_locked( slot ) )
         {
-            ++stats->unlocked_slots;
+            ++stats->locked_slots;
         }
         if( ! psa_is_key_slot_occupied( slot ) )
         {