using System;

public class Program

{

    public class YearsMonths {

        public int Years;

        public int TotalMonths;

        public int Months;

    }

    public static void Main()

    {

        var diffs = YearMonthDiff(new DateTime(2013, 12, 1), DateTime.Today);

        Console.WriteLine("TotalMonths: " + diffs.TotalMonths);

        Console.WriteLine("Years: " + diffs.Years);

        Console.WriteLine("Months: " + diffs.Months);

    }

    public static YearsMonths YearMonthDiff(DateTime startDate, DateTime endDate) {

        // Simply subtracting Month won't work as Jan 2014 will be less than Dec 2013.

        // So first multiply the month with year to get absolute month

        int monthDiff = ((endDate.Year * 12) + endDate.Month) - ((startDate.Year * 12) + startDate.Month) + 1;

        int years = (int)Math.Floor((decimal) (monthDiff / 12));

        int months = monthDiff % 12;

        return new YearsMonths {

                TotalMonths = monthDiff,

                Years = years,

                Months = months

            };

    }

}