Why use banker's rounding to round numbers ending in 5

[Yashbhatt]

There is a specific rule(Banker's Rule I think) for rounding of numbers that end in 5. The rule is that we add 1 to the preceding digit of it's odd but keep it as it is if it's even. It's always keeping it even.

Why is this rule applied? I read something like it is done to prevent biased rounding off our something.

 

[bhillyard]

Yes, in the long run rounding up if the next digit is a five or more will bias the result upwards. Rounding to an even digit will tend to even this out.

 

[Yashbhatt]

Ok. Thanks.