how to find the solution for to find the difference between last two entries in Mysql : I need a solution regarding the Fine the difference between the last two entries difference in mysql

SELECT DATE_FORMAT(order_datetime,'%m/%Y') as date, SUM(order_total_after_tax) as number FROM tbl_order where status='Confirmed' GROUP BY DATE_FORMAT(order_datetime,'%Y/%m') Limit 2

OutPut : 
date     number
02/2019 2345.01
03/2019 103751.05



But i need exact soltion is i need to find difference between the last 2 result  

2345.01 -103751.05 

Result : -101406.04  
how to do in mysql What is the Query ?


  