by half
(colloquial) By far; by a long chalk; to an excessive extent or degree, especially to the extent that it is negative, gets in the way, etc.
Little Miss Smartyboots is too clever by half.
According to the World Bank, Algeria is making progress toward its goal of "reducing by half the number of people without sustainable access to improved drinking water and basic sanitation by 2015". Source: Internet
Air pollution in Birmingham 'shortens lives of children by half a year' Source: Internet
An attack in 1969 would likely have been carried out by half as many troops but with more firepower, supported by modern armor, artillery, tactical air forces and possibly even tactical nuclear weapons. Source: Internet
Authorities say traffic in the Twin Cities has dropped by 47%, and by half in the rest of the state, but highway fatalities have doubled. Source: Internet
British attacks in Europe and Asia reduced the VOC fleet by half; removed valuable cargo from its control; and devastated its remaining power in Asia. Source: Internet
A series of famines and plagues, such as the Great Famine of 1315–1317 and the Black Death killed people in a matter of days, reducing the population of some areas by half as many survivors fled. Source: Internet