help with Dax

[Rank237]

I am trying to find the % of people retained Day over from my data set. However, I am having an issue getting my Dax working correctly. is there any way I get some help with it? 

DAYS	Customer	Retained customer	Retained customer Fall to Spring
0	2512	2510	2314
1	2510	2508	2313
2	2510	2508	2313
3	2510	2508	2313
5	2510	2508	2313
6	2512	2510	2314
7	2512	2510	2314
8	2511	2509	2313
9	2511	2509	2313
10	2511	2509	2313
11	2511	2509	2313
12	2511	2509	2313
13	2510	2508	2313
14	2506	2504	2312
15	2504	2502	2311
16	2503	2501	2310
17	2503	2501	2310
18	2501	2499	2308
19	2504	2502	2308

[amitchandak]

@Rank237 , is this your raw data or final outcome?

refer, if these can help

Customer Retention Part 1:
https://community.powerbi.com/t5/Community-Blog/Customer-Retention-Part-1-Month-on-Month-Retention/b...
Customer Retention Part 2: Period over Period Retention :https://community.powerbi.com/t5/Community-Blog/Customer-Retention-Part-2-Period-over-Period-Retenti...

Customer Retention with Dynamic Segmentation, New/Lost/Retain Customer Count: https://www.youtube.com/watch?v=W4EF1f_k6iY

The information you have provided is not making the problem clear to me. Can you please explain with an example.

Appreciate your Kudos.