Is "in" worth it? №1

using System;
using System.Collections.Immutable;
using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Jobs;
using BenchmarkDotNet.Running;

namespace Benchmark
{
    [SimpleJob(RuntimeMoniker.CoreRt50)]
    public class Md5VsSha256
    {
        [Params(10, 100, 1000)]
        public int N;

        private ImmutableArray<int> data;

        [GlobalSetup]
        public void Setup()
        {
            var random = new Random();

            var builder = ImmutableArray.CreateBuilder<int>(N);
            for (int i = 0; i < N; ++i)
            {
                builder.Add(random.Next());
            }
            data = builder.MoveToImmutable();
        }

        static int ViaRef(in ImmutableArray<int> array)
        {
            int sum = 0;
            foreach (var i in array)
            {
                sum += i;
            }
            return sum;
        }

        static int ViaValue(ImmutableArray<int> array)
        {
            int sum = 0;
            foreach (var i in array)
            {
                sum += i;
            }
            return sum;
        }

        [Benchmark]
        public int Ref()
        {
            return ViaRef(data);
        }

        [Benchmark]
        public int Value()
        {
            return ViaValue(data);
        }
    }

    public static class Program
    {
        public static void Main()
        {
            BenchmarkRunner.Run<Md5VsSha256>();
        }
    }
}