Rounding to Even
Personify uses "Banker's rounding" (or Gaussian
rounding), which is different from standard rounding (rounding to the nearest number).
With the round-to-even rule, when the remainder at the rounding position is .5,
that number is rounded up when the number before it is odd, and rounded down
when the number before it is even. For example, the number 6.5, using the
round-to-even rule, would round down to the even number 6.0, while the number
7.5 would round up to the even number 8.0 -- hence the name round-to-even rule.
Banker’s rounding was implemented in Personify to mitigate
the skewing of data when large amounts of data are used, as used by banks. The
round-to-even rule (in theory) rounds half of things up and half of things down
when a five is involved, rather than rounding everything up when a 5 is
involved.