How many years did Cleisthenes democracy last in athens

The late 570s BCE basically at the end of the 6th century

Cleisthenes (b. late 570s BCE) was an Athenian statesman who famously reformed the political structure and processes of Athens at the end of the 6th century BCE and, thereby, greatly increased the influence of ordinary citizens on everyday politics. Accordingly, he is credited with creating a celebrated system of democracy, which, over the following decades, would become ever more direct so that all citizens could actively and directly participate in government.