Question: how is phrf corrected time calculated?
Answer: Time on Time (TOT) also uses our PHRF ratings but calculates time corrections as follows: Corrected time = Elapsed time X 650/(550 + PHRF). For example, if your PHRF rating was 120 and it took you 63.5 minutes to finish the race, your corrected time would be 63.5 X 650/670 = 61.6 minutes.