miscalculate
verb [ I or T ]
uk/mɪsˈkælkjəleɪt/ us ACCOUNTING
to calculate an amount wrongly:
The water company had deliberately miscalculated the data it supplies to the regulator.
The insurance company admitted that it had miscalculated one of its pension funds by around £15m.
to judge a situation badly:
The biggest problem was that the airlines miscalculated demand.
badly/seriously/horribly miscalculate The Dutch had badly miscalculated just how much London would control the newly merged companies.