Examples of Centrally Planned Economies

"Communist and socialist systems are the most noteworthy examples in which governments control facets of economic production. Central planning is often associated with Marxist-Leninist theory and with the former Soviet Union, China, Vietnam, and Cuba. While the economic performance of these states have been mixed, they've generally trailed capitalist countries, in terms of growth." — Source

Yeah, I don't know what definitions you go by, but generally speaking, people do believe that communism has been attempted many times. The fact that it turns authoritarian is because it's impossible to achieve with the same level of success as market economies, which by the way, utilize the wisdom of the many for the good of the many. ☭ You see that, we're already communist and you don't like it. What makes you think you'd like even more communism to put on your communism? This is fixing to turn into one of those horrible Xhibit memes. : -)