"She grew" is a past tense construction. "She has grown" is a present tense construction. ... We call "She grew" a past indefinite construction, or a simple past construction. We call "She has grown" a present perfect construction.

Is has grown correct?

The correct answer would be (as John Lawler said): In the last years, the number of some-things has grown. This is because the event of the number growing is relevant to your (supposed) focus on the present.

Have grown up or has grown up?

"He has grown" is usually used to mean he is now taller than when he was a child, or just physically bigger in general. But "He has grown up" when said on its own usually means "He no longer acts like a child".