Difference between 2 columns in a sheet

Version 3

    I am very new to tableau and has been tasked to create the below output. It will be a great help if someone can help me out.

    I Have data in the Account Table where we have data for every month called period.

    The account is associated with different product type

    Need to have variance in number of account per product type compared to the last period(Period 10-Period 9). i.e. number of accounts increased per product between 2 periods in one sheet as shown in the output.

    Below is the sample output..

    Joe Mako

     

    Perod 9Period 10
    Product_TypeTotal AccountTotal AccountVariance(Difference)%Variance
    ATM34133%
    CHEC253150%
    CCD3300%

     

    Below is the Sample data

     

    Acct_NoProduct_TypePeriod
    1ATM9
    2ATM9
    3ATM9
    4CHEC9
    5CHEC9
    6CCD9
    7CCD9
    8CCD9
    1ATM10
    2ATM10
    3ATM10
    4CHEC10
    5CHEC10
    6CCD10
    7CCD10
    8CCD10
    9CHEC10
    10CHEC10
    11CHEC10
    12CHEC10