What's faster `i < list.size()` or `i < size` where size is precomputed?

Loop.cpp

// My Results: VS 2017, Debug x86 Start-Without-Debugging, i7-4790K 4.0GHz 32.0GB RAM
//
// FunctionCondition 1 = 1783293664
// 369820712 ns
// VariableCondition 1 = 1783293664
// 229243798 ns
// FunctionCondition 2 = 1783293664
// 368293487 ns
// VariableCondition 2 = 1783293664
// 226769355 ns
// FunctionCondition 3 = 1783293664
// 370692645 ns
// VariableCondition 3 = 1783293664
// 226774989 ns
//
// Results, storing the size in a variable is consistently 39% faster.

#include "pch.h"
#include <iostream>
#include <vector>
#include <chrono>

using namespace std;

#define LOOPS 1000000

int FunctionCondition(vector<int>& list)
{
	int sum = 0;
	for (int i = 0; i < list.size(); i++) {
		sum += list[i];
	}
	return sum;
}

int VariableCondition(vector<int>& list)
{
	int sum = 0;
	int size = list.size();
	for (int i = 0; i < size; i++) {
		sum += list[i];
	}
	return sum;
}

int main()
{
	vector<int> list = vector<int>(LOOPS);
	for (int i = 0; i < LOOPS; i++) {
		list[i] = i;
	}

	{
		auto start = chrono::steady_clock::now();
		cout << "FunctionCondition 1 = " << FunctionCondition(list) << std::endl;
		auto end = chrono::steady_clock::now();
		cout << (end - start).count() << " ns" << std::endl;
	}

	{
		auto start = chrono::steady_clock::now();
		cout << "VariableCondition 1 = " << VariableCondition(list) << std::endl;
		auto end = chrono::steady_clock::now();
		cout << ( end - start ).count() << " ns" << std::endl;
	}

	{
		auto start = chrono::steady_clock::now();
		cout << "FunctionCondition 2 = " << FunctionCondition(list) << std::endl;
		auto end = chrono::steady_clock::now();
		cout << ( end - start ).count() << " ns" << std::endl;
	}

	{
		auto start = chrono::steady_clock::now();
		cout << "VariableCondition 2 = " << VariableCondition(list) << std::endl;
		auto end = chrono::steady_clock::now();
		cout << ( end - start ).count() << " ns" << std::endl;
	}

	{
		auto start = chrono::steady_clock::now();
		cout << "FunctionCondition 3 = " << FunctionCondition(list) << std::endl;
		auto end = chrono::steady_clock::now();
		cout << ( end - start ).count() << " ns" << std::endl;
	}

	{
		auto start = chrono::steady_clock::now();
		cout << "VariableCondition 3 = " << VariableCondition(list) << std::endl;
		auto end = chrono::steady_clock::now();
		cout << ( end - start ).count() << " ns" << std::endl;
	}
}