diff --git a/inc/Performance.h b/inc/Performance.h
index a9daf2c..5e5ef56 100644
--- a/inc/Performance.h
+++ b/inc/Performance.h
@@ -90,13 +90,13 @@ private:
   static Performance* instance;
   Performance();
 
-  uint64_t data_memory_read = 0;
-  uint64_t data_memory_write = 0;
-  uint64_t code_memory_read = 0;
-  uint64_t code_memory_write = 0;
-  uint64_t register_read = 0;
-  uint64_t register_write = 0;
-  uint64_t instructions_executed = 0;
+  uint64_t data_memory_read;
+  uint64_t data_memory_write;
+  uint64_t code_memory_read;
+  uint64_t code_memory_write;
+  uint64_t register_read;
+  uint64_t register_write;
+  uint64_t instructions_executed;
 };
 
 #endif
diff --git a/src/Performance.cpp b/src/Performance.cpp
index 122e48c..6259af9 100644
--- a/src/Performance.cpp
+++ b/src/Performance.cpp
@@ -11,7 +11,15 @@ Performance* Performance::getInstance()
 }
 
 Performance::Performance()
-{}
+{
+    data_memory_read = 0;
+    data_memory_write = 0;
+    code_memory_read = 0;
+    code_memory_write = 0;
+    register_read = 0;
+    register_write = 0;
+    instructions_executed = 0;
+}
 
 void Performance::dump() {
   cout << dec << "# data memory reads: "  << data_memory_read << endl;