Lapsed and Reactivated customers

Hello all,

I am new to Power BI, I am trying to create a report where needs to calculate total lapsed customers and reactivated customers.

Lapsed customers : 

Customers who are not made any sales for last 12 months . Example If we take June 2018 , it should look back 12 months get number of customers who have not made any sales.

Reactivated customers: 

Customers who purchased after 12months of lapsed period. Example If we take June 2018 it should only count customers who have not made any sales for last 12 months but purchased this month. 

I have looked few examples here like below :

http://community.powerbi.com/t5/Desktop/Calculating-lapsed-and-reactivated-customers-month-by-month/m-p/249240#M110530

As I am new ,what I have done so far is I have loaded data into file (Table name :' Value Entry'  and fields are 'Customer No_','Posting Date ' (format '2018-07-16 00:00:00.000') and 'Order No_'.  Would I need any more fields ? 

And I know I have to create a measure by DAX. Please help me with the script.

Thanks in advance for your time.

Madhu