If you mean you want the value to be randomly changing with the number constantly staying within certain parameters, you can do it with wiggle. Say you want it to be between 25 and 75. Make it 50 and add a wiggle expression like wiggle(1,25) Every 1 second the value will shift +/- 25 from 50, meaning, it's going down as far as 25 or as high as 75.
- The Great Szalam
(The 'Great' stands for 'Not So Great, in fact, Extremely Humble')
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