diff --git a/experiments.py b/experiments.py
index 9894453..672ead4 100644
--- a/experiments.py
+++ b/experiments.py
@@ -670,7 +670,7 @@ def local_train_net_scaffold(nets, selected, global_model, c_nets, c_global, arg
         logger.info("net %d final test acc %f" % (net_id, testacc))
         avg_acc += testacc
     for key in total_delta:
-        total_delta[key] /= len(selected)
+        total_delta[key] /= args.n_parties
     c_global_para = c_global.state_dict()
     for key in c_global_para:
         if c_global_para[key].type() == 'torch.LongTensor':