it's 2^32 / 2
(2.18 billion?)
it's an overflow problem that you can avoid by applying the financial coefficient setting. it'll read >2.18 billion, but it's not actually beyond the memory footprint of that particular variable, or anything that works with that number that could result in an overflow.
it's trying to do the math, but it ran out of little counter beads! it only has a couple billion positive ones
the negative 2.18 billion doesn't help much, but it's got to be 'signed'