But now the LORD has spoken, saying,
Within three years, like the years of a hireling, and the glory of Moab shall be despised, with all that great multitude; and the remnant shall be very small and feeble.
Read Chapter 16
George Leo Haydock
Not many. It was laid waste in the third year of Ezechias. But its final destruction took place only five years after that of Jerusalem. (Calmet)
The wars against Moab continued three years, after which it was reduced to servitude. (Worthington)