What are some examples of successful matriarchal and patriarchal societies in the 21st century?

Define "successful"

Clarify what makes a society matriarchal or patriarchal.

1 hour ago, Mr Rayon said:

What are some examples of successful matriarchal and patriarchal societies in the 21st century?

right or wrong only exists in hindsight...

and only now...

Define "patriarchal" or "matriarchal". In traditional terms: patriarchal = higher fertility rates. Matriarchal - higher participation of woman in economy = higher productivity (for the same amount of population). Therefore matriarchal is more successful when high fertility strategy goes into a dead end or when low fertility rates problem is solved.

Do we even have any matriarchal data? As far as I know, today's western world is only 40-45% matriarchal, and the closest we've ever been to female dominans.

I suspect that the answer to "Does society tend to flourish better when it's patriarchal or matriarchal?" is "no".

1 hour ago, QuantumT said:

Do we even have any matriarchal data? As far as I know, today's western world is only 40-45% matriarchal, and the closest we've ever been to female dominans.

That is not the typical definition of matriarchy. The latter defines a system where structurally the power (can be socially or politically) is held by women. For women to be able to achieve power. In the Western world (but also historically in most other places) current systems were borne or developed from patriarchic systems though some structural elements (but not all) have eroded, it is still very much so in practice.