Okay Sam, let’s clear this up.
See photo below for the starting point.
I’ve used your formulas for this, I’ve made only a little change for “Customer Lost” and for “Customer Revenue Lost”, both are negative now:
At this point I want us to concentrate on the “Customers Steady”.
I want to divide the steady customers in the following segments:
Lost Revenue – Steady Revenue – Won Revenue
2015:
There are 3 Customers Steady (customer 1, 2 and 3).
Customer 1: Revenue 2015 -/- Revenue 2014 = 45 -/- 25 = 20 = Won Revenue
Customer 2: Revenue 2015 -/- Revenue 2014 = 38 -/- 40 = - 2 = Lost Revenue
Customer 3: Revenue 2015 -/- Revenue 2014 = 27 -/- 35 = - 8 = Lost Revenue

Check number of Customers:
There were 4 customers at the end of 2014. We lost in 2015 1 customer and we won 4 customers.
At the end of 2015 we have 7 customers (4 -/- 1 +/+ 4). The report gives the right number.
Check amount of Revenue:
The revenue for 2014 was 112, the revenue for 2015 was 275. The positive difference is 163, what’s happened in 2015?
Customer Revenue Lost:
We lost customer 4 in 2016, revenue lost is -12;
Steady customers:
Lost Revenue steady customers = -10 (customers 2 and 3)
Won Revenue steady customers = 20 (customer 1)
New Customers Sales:
The new customers in 2015 were customers 5, 6, 7 and 8, won revenue: 165
Check the amount:
112 -/- 12 -/- 10 +/+ 20 +/+ 165 = 275, the Total Sales in the report is giving the right amount.
I hope you understand now what I want, if not, then I have to look for another way to explain it to you.
Hopefully you can help me with the formulas for the customers steady.
Thanks in advance,
Regards,
Cor