Lifetime Cost

The cost of attracting and retaining a potential customer over the lifetime of the cohort.  

This metric takes into account all costs incurred by the business for a potential client in the cohort. It differs from CPA in that it takes into account not only the cost of attracting, but also the cost of retaining a scaling unit in the cohort. 

To calculate this metric you just need to add up all the costs for one scaling unit during the life of the cohort, for this purpose I recommend to use the fixation of all touches of a scaling unit with the product with the indication of the channel from which the scaling unit came, as well as the cost of this transition.