Pick a clock and stick with it
Scores from a one-second round and a sixty-second round are different measurements. Choose the clock that matches what you care about and keep using it, otherwise the tally sheet cannot tell you anything.
Technique, roughly ranked
Regular clicking tops out around 8 to 10 CPS for most people. Jitter clicking gets you into the low teens. Butterfly clicking often reaches 15 to 20. Drag clicking can exceed 25 but depends heavily on the mouse.
Your mouse sets a ceiling
Every mouse applies debounce, a short delay that stops one press from registering twice. Longer debounce means a lower maximum CPS. Some gaming mice let you adjust it in their software.
Warm up, then test
Hands are measurably slower when cold. Two or three easy rounds before a serious attempt give a fairer number.
Stop at the first ache
Rapid clicking puts load on small tendons. Short sessions with breaks are better for progress and for your wrist than long grinding blocks.