Reading with vector::data()[] seems faster than vector[]

I did this small console test using Visual Studio 2019 fully updated, and executing this in release mode using Ctrl-F5.

    // 1. I generate a random vector
    std::vector<int> vectorVal;
    for (int i=0; i!=32; ++i)
    {
        vectorVal.push_back(i-3);
    }

    // 2. Then I perform some reads
    int uselessValue = 0;
    auto start = high_resolution_clock::now(); // I take initial time
    for (int i = 0; i < 10000; ++i)
    {
        for (int j=0; j!=32; ++j)
        {
            // uselessValue += (vectorVal.data()[j]? +1 : -1); // Faster!!!!
            uselessValue += (vectorVal[j]? +1 : -1); // Slower
        }
    }
    auto end = high_resolution_clock::now(); // and end time

    // 3. Last, I show the time it needed to perform the operations
    std::cout<<"Vector "<<uselessValue<<": \t"<<duration_cast<nanoseconds>(end-start).count()<<" nanoseconds.\n"<<std::endl;

If you execute this, the result are around 80000 nanoseconds on my computer. However, if you use the "Faster" line instead the "Slower" one, the result is 100 nanoseconds.

I tried to debug this to see what's happening. Basically it should do the same, access to a basic C array, but it seems much faster with the vectorVal::data()[]. I'm quite sure I'm doing something wrong in my testing, but I fail to realize what's wrong.

Why does seem faster using vector::data()[] than vector[] to access its content?

Here's the full source code:

    const int num = 10000;

{
    std::vector<int> vectorVal;
    for (int i=0; i!=32; ++i)
    {
        vectorVal.push_back(i-3);
    }
    int uselessValue = 0;
    auto start = high_resolution_clock::now();
    int* data = vectorVal.data();
    for (int i = 0; i < num; ++i)
    {
        for (int j=0; j!=32; ++j)
        {
            uselessValue += (vectorVal.data()[j]? +1 : -1);
        }
    }
    auto end = high_resolution_clock::now();
    std::cout<<"Vector-data"<<uselessValue<<": \t"<<duration_cast<nanoseconds>(end-start).count()<<" nanoseconds.\n"<<std::endl;
}

{
    std::vector<int> vectorVal;
    for (int i=0; i!=32; ++i)
    {
        vectorVal.push_back(i-3);
    }


    int uselessValue = 0;
    auto start = high_resolution_clock::now();
    for (int i = 0; i < num; ++i)
    {
        for (int j=0; j!=32; ++j)
        {
            uselessValue += (vectorVal[j]? +1 : -1);
        }
    }
    auto end = high_resolution_clock::now(); 
    std::cout<<"Vector "<<uselessValue<<": \t"<<duration_cast<nanoseconds>(end-start).count()<<" nanoseconds.\n"<<std::endl;
}

I've uploaded the Visual Studio 2019 project solution here, you may download it and test directly. Maybe I'm failing with my settings.