Should a .NET generic dictionary be initialised with a capacity equal to the number of items it will contain?

Question

If I have, say, 100 items that\'ll be stored in a dictionary, should I initialise it thus?

var myDictionary = new Dictionary(100);
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Answer 1

I did a quick test, probably not scientific, but if I set the size it took 1.2207780 seconds to add one million items and it took 1.5024960 seconds to add if I didn't give the Dictionary a size... this seems negligible to me.

Here is my test code, maybe someone can do a more rigorous test but I doubt it matters.

static void Main(string[] args)
        {
            DateTime start1 = DateTime.Now;
            var dict1 = new Dictionary(1000000);

            for (int i = 0; i < 1000000; i++)
                dict1.Add(i.ToString(), i.ToString());

            DateTime stop1 = DateTime.Now;

            DateTime start2 = DateTime.Now;
            var dict2 = new Dictionary();

            for (int i = 0; i < 1000000; i++)
                dict2.Add(i.ToString(), i.ToString());

            DateTime stop2 = DateTime.Now;

            Console.WriteLine("Time with size initialized: " + (stop1.Subtract(start1)) + "\nTime without size initialized: " + (stop2.Subtract(start2)));
            Console.ReadLine();
        }