Percentage Variance in List Row Summary

[AnuElza]

Hi,

I have a report query which is a "union" of say query1 and query2.
Query1:
Year      Qty
2017     50

Query 2:
Year    Qty
2018    70

Report: List shows data like this;

Year   Qty
2017   50
2018    70
% diff   40%  -->(70-50)/50*100
now, How can I show a list summary as a percentage variance of qty? Is it even possible to show?

Appreciate your time.

Thanks.