What were the effects of the Persian Wars on Athens' economy?

Answer 1

It saw the re-empowerment of the ruling class which had led the resistance to the Persian invasion, setting back the transition to democracy underway for the previous generation.

It took a new push led by Ephialtes two decades later to reinvigorate the democratic push.

Answer 2

During the final phase of the war, Athens led the Delian league to which other cities contributed either ships of money. Most found it easier to give money, so Athens was able to maintain a superior fleet and continue to extort the money even after peace was made with Persia.

This money was diverted to beautifying the city and keeping half its population on the public payroll, as well as keeping up the dominant naval power to continue collecting the money and extend Athens' commercial interests.