I have encountered this issue in my .NET Framework 4.8 project, but it also can be reproduced in .NET 8 (https://learn.microsoft.com/en-us/dotnet/api/system.math.round?view=net-8.0#code-try-2).
// incorrect rounding (double)
Console.WriteLine(Math.Round(71.335, 2, MidpointRounding.AwayFromZero)); // 71.33 (must to be 71.34)
Console.WriteLine(Math.Round(72.335, 2, MidpointRounding.AwayFromZero)); // 72.33 (must to be 72.34)
Console.WriteLine(Math.Round(73.335, 2, MidpointRounding.AwayFromZero)); // 73.33 (must to be 73.34)
// correct rounding (double)
Console.WriteLine(Math.Round(60.335, 2, MidpointRounding.AwayFromZero)); // 60.34
Console.WriteLine(Math.Round(83.335, 2, MidpointRounding.AwayFromZero)); // 83.34
// correct rounding (decimal) which was incorrect for double
Console.WriteLine(Math.Round(71.335M, 2, MidpointRounding.AwayFromZero)); // 71.34
Console.WriteLine(Math.Round(72.335M, 2, MidpointRounding.AwayFromZero)); // 72.34
Console.WriteLine(Math.Round(73.335M, 2, MidpointRounding.AwayFromZero)); // 73.34
I don’t understand what is the difference between 71.335, 72.335, etc. and 60.335, 83.335, etc. which makes Math.Round() behave differently.
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