firsttime is a flag.
When it is set i.e. 1, you lock in the start time which subsequently is used in the calculations.
Suggest you use a name like firstTimeFlag.
BTW
Use CTRL T to format the sketch.
Please use code tags.
Use the </> icon in the posting menu.
[code] Paste sketch here. [/code]
I am sure if you think about it a bit, you can figure out how to control printing the way you need.
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