Bob Cratchit is a fictional character in the Charles Dickens novel A Christmas Carol. The abused, underpaid clerk of Ebenezer Scrooge (and possibly Jacob Marley, when he was still alive), Cratchit has come to symbolize poor working conditions, especially long working hours.
According to a comment by his wife, Cratchit works for 15 shillings a week at a rate of three pence ("thruppence") an hour for 60 hours per week. Until the decimalization of the British Pound in 1971, one shilling was twelve pence. Thus, fifteen shillings is 180 pence. It would take 60 hours to earn 180 at a rate of three pence per hour. In terms of 2015 purchasing power, this would be approximately £63.00 or about $94 US per week.