struct TimeSpan {
    long ticks;
    const int TicksPerSecond = 10000000;
    const int TicksPerMillisecond = 10000;

    public double TotalMilliseconds {
       get {
           return ticks / (double)TicksPerMillisecond;
       }
    }

    static void Main()
    {
        TimeSpan foo, bar;

        // this value uses 30 bits
        foo.ticks = 1000000000L;
        bar.ticks = foo.ticks + 10;
        System.Console.WriteLine("Delta: {0:0.0000}ms", bar.TotalMilliseconds - foo.TotalMilliseconds);

        // this value uses 50 bits
        foo.ticks = 1000000000000000L;
        bar.ticks = foo.ticks + 10;
        System.Console.WriteLine("Delta: {0:0.0000}ms", bar.TotalMilliseconds - foo.TotalMilliseconds);

        // this value uses 60 bits
        foo.ticks = 1000000000000000000L;
        bar.ticks = foo.ticks + 10;
        System.Console.WriteLine("Delta: {0:0.0000}ms", bar.TotalMilliseconds - foo.TotalMilliseconds);
    }
}