Actually, Enum.into/3 would suffice:
|> Enum.into(%{
[state: "active", health: "healthy"] => 0,
[state: "active", health: "unhealthy"] => 0,
[state: "paused", health: "healthy"] => 0,
[state: "paused", health: "unhealthy"] => 0
}, fn {{state, health}, v} -> {[state: state, health: health], Enum.count(v)} end)
