QUEST DIAGNOSTICS INC COM STK USD0.01 revenue for the last year amounted to 9.25 B USD, the most of which — 8.98 B USD — came from its highest performing source at the moment, Diagnostic Information Services, the year earlier bringing 9.61 B USD. The greatest contribution to the revenue figure was made by United States — last year it brought QUEST DIAGNOSTICS INC COM STK USD0.01 9.25 B USD, and the year before that — 9.88 B USD.