Hi Sandor,
As Samuel mentioned you can see every attempt in the Campaign view.
But if you'd like to keep track of this in the contact list, you'd need to have a custom column and create a wrap-up rule where you just increment value in that custom coulmn by one each time.
You need to make sure the rule always kick off, I'd suggest using some column that you know always has a value as Condition, and than in Action increment the value.
In this example I am using column Name as my condition, where I know that my column Name doesn't have value 0. Then I increment a custom column with 1.

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Hermina Cosic
Senior Solution Architect
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