Combining results of multiple queries into a single report

My company is new to jasper reports and I'm trying to create what I believe to be a relatively simple report but I'd like to know the best way to approach this. I've created a relatively simple query to return sales for the current year by account.

Example:

Now I want to add another column for Last Year's Sales. It's simple enough to build the query, but how do I now add this as a column?

- Create a subreport for Last Year's Sales with Account as a parameter and Sales as a return variable?

- Similar to the above, but using a subdataset?

Obviously, I can do this using a complex SQL statement but I don't feel like that's the best way. (Also, I plan to add some other columns to this report that may not be so easy to do by extending a complex sql query).

Thanks for any help. I have found the documentation and Online Learning Portal to be a bit lacking for anything but the basics, so if there's any resurces out there for dealing with more complex reports that would be greatly appreciated as well.