The firms that appear in Global London are the 50 largest non-UK originated firms in London, ranked by headcount. Partner and lawyer numbers were all requested as full-time equivalents as of 1 January 2014. All partner hires were up to and including February 2014. Total lawyer numbers include partners, associates, assistants and trainees but not paralegals. The US Internal Revenue Service average exchange rate for the year 2013 was used for Global London calculations. This was $1=£0.665.