Hello @Stephan2,
The very easiest solution is to use the Data Store to store your variable value.
Just create it with, fetch, and update it as progress progresses.
When it reaches to 60 then update it to 1. Need to use routers and Filters to check things.
Read more about Data Stores here https://www.make.com/en/help/tools/data-store#data-store-935244
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