Why does .NET use banker’s rounding as default?

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According to the documentation, the decimal.Round method uses a round-to-even algorithm which is not common for most applications. So I always end up writing a custom function to do the more natural round-half-up algorithm:

public static decimal RoundHalfUp(this decimal d, int decimals)
{
    if (decimals < 0)
    {
        throw new ArgumentException("The decimals must be non-negative", 
            "decimals");
    }

    decimal multiplier = (decimal)Math.Pow(10, decimals);
    decimal number = d * multiplier;

    if (decimal.Truncate(number) < number)
    {
        number += 0.5m;
    }
    return decimal.Round(number) / multiplier;
}

Does anybody know the reason behind this framework design decision?

Is there any built-in implementation of the round-half-up algorithm into the framework? Or maybe some unmanaged Windows API?

It could be misleading for beginners that simply write decimal.Round(2.5m, 0) expecting 3 as a result but getting 2 instead.

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