Long-term energy consumption and public employment growth, moreover, have typically lain considerably above population growth, creating an increasing cost burden.
Moreover, the cuts will come after a decade of public spending growth.
Two states with record public investment growth in the same month?
£20bn would be found by reducing inefficiency, limiting public pay growth and cutting lower-priority spending.
"The only thing holding digital public library growth back is low book-buyer awareness," Mr. Hildick-Smith said.
Meanwhile, the government's need to contain the fiscal deficit means that public consumption growth also will be significantly curtailed.
Andrew Smith, economist at KPMG said: "With a sharp slowdown in public spending growth now inked in from 2008, significant improvements in public services are dependent on productivity gains.
Public spending growth will be pared back from 1.8% a year to 1.2% - the lowest increases since Labour's first two years in office in the late 1990s.
Rather, the measures were sold as a vital period of pain in order to create a platform for much-needed public spending growth in the future.
Without them the British economy – and by extension pensions, public services, growth, prosperity – would have shrivelled to a significant extent or taxes would have had to rise.
