eCPI 계산하는 방법 (Find out how to find the real cost of an App Install)

https://growthbug.com/download-effective-cpi-cost-per-app-install-calculator-8c82056ce6eb

Finding the cost of your app install is simple — price (CPI) you pay to a network? Think again — is it the actual cost of each net install? Here is a quick math on how to calculate it accurately (excel calculator available below to download):

You need to have the following 3 basic numbers available to start with:
Price you pay per install: CPI paid to network
Average uninstall rate: Available from Android App Store dashboard
K Factor (How many organic install brought in by a paid one): Varies as per the rank bucket— check the table below.

K Factor Table:
Apps ranked between 1 to 10 = 2.5
Apps ranked between 11 to 25 = 1.5
Apps ranked between 26 to 50 = 1
Apps ranked between 51 to 100 = 0.5
Apps above 101 = 0.1
(Note: Rank in overall Free or Overall Paid section)

So now lets take an example and find App’s effective CPI:
Example 1: App ranked between 11 to 25
(A) Install Recd: 1
(B) CPI Charged by Network: $2.5
(C) Total Paid to Network: A x B = $2.5
(D) Uninstall Rate: 40%
(E) Net Installs: A*(1-D) = 0.6
(F) K Factor: 1.5 (Refer table above)
(G) Organic Install: E x F = 0.9
(H) Total Installs = E + G= 1.5
Effective CPI = C/ H= $1.67

So in above example your effective cost of getting an install is $1.67

Now lets see how the math changes if your app is ranked below 100:
Example 2: App ranked below 100
(A) Install Recd: 1
(B) CPI Charged by Network: $2.5
(C) Total Paid to Network: A x B = $2.5
(D) Uninstall Rate: 40%
(E) Net Installs: A*(1-D) = 0.6
(F) K Factor: 0.1 (Refer table above)
(G) Organic Install: E x F = 0.06
(H) Total Installs = E + G = 0.66
Effective CPI = C / H = $3.79

To make things easy, I am attaching a CPI calculator made in excel which helps you input your app’s details and find out the true CPI.
Download here — http://bit.ly/CPIcalc

Update: Thanks to Sandeep Amar, he pointed one big mistake I made while calculating Effective CPI. Updated the excel sheet as well. Thank you Sandeep