Prometheus Kong Plugin - Request latency


I configured prometheus plugin to fetch request latency which I understand is the the time between first byte from client to last byte from server (response). however, in order to verify the timing I run the command curl -w "@curl-format.txt" -o /dev/null -s https://example-test/applications to fetch the total time

        time_connect:  0.183496s
     time_appconnect:  0.377288s
    time_pretransfer:  0.377404s
       time_redirect:  0.000000s
  time_starttransfer:  0.724355s
          time_total:  0.724818s

Request type latency : 163 ms

And the two values are different. Am I missing anything ?

Thank you