There was dissatisfaction with the dictionaries of the period, so in June 1746 a group of London booksellers contracted Johnson to write a dictionary for the sum of 1,500 guineas (£1,575), equivalent to about £220,000 in 2015.[1] Johnson took nearly nine years to complete the work, although he had claimed he could finish it in three. Remarkably, he did so single-handedly, with only clerical assistance to copy out the illustrative quotations that he had marked in books. Johnson produced several revised editions during his life.