Yes each year is separate. But if you know what you need to enter you can buy a lower version like Deluxe. All the Desktop programs have the same forms. You just get more help and guidance in the higher versions.
Buy 2017 here
https://turbotax.intuit.com/personal-taxes/past-years-products/ Buy 2018 here
https://turbotax.intuit.com/personal-taxes/cd-download/
