I was part of a team that maintained end of day commodity trading software for a bank. Out of nowhere they got an $800 million inbalance one night. It was very odd and of such a magnitude that it was seen at board level (not good). We spent 12 nights watching end of days and debugging it in production before we found the issue.
It turned out that a new type of trade had been introduced which had a 0 days length. No trade we handled had ever had a zero day length; it was unheard of and the software did a divide by the trade length without checking for zero hence the bam. The div by zero exception was caught but only after it had skipped a Yen to $ fx conversion which is why the inbalance was so large.
It turned out that a new type of trade had been introduced which had a 0 days length. No trade we handled had ever had a zero day length; it was unheard of and the software did a divide by the trade length without checking for zero hence the bam. The div by zero exception was caught but only after it had skipped a Yen to $ fx conversion which is why the inbalance was so large.