If you stretch the definition of "immigrant", it's possible that some mass-migrations might count - perhaps the Partition of India, which was an economic disaster for Pakistan?

People who lament the coming of migrant people are rarely concerned for their "nation's economic health," they are worried about their own power and wealth within the society. Nativist elements are usually attempting to preserve the existing power structure of the state because they are either on top, or perceive themselves to be on top. The United States, for example, has had a strong economy for a long time despite being composed of various waves of migrant people; some temporary and some permanent. However, with each wave the balance of power for the previously established groups has been disrupted. This is why you will also see the descendants of migrants, or perhaps even well established immigrant people themselves oppose future immigration.

Lets look more specifically. In the United States WASP (White Anglo-Saxon Protestant) people have been slowly "losing" power for centuries, yet the nation is not in ruins; though, I am sure some would disagree with me. I won't go into issues of privilege here, there are obviously still advantages to being a white male in the United States, but they are rarely structural or legal. There are a few obvious example of the slowly changing power structures in the United States. The US Supreme Court, for example, doesn't have a single WASP on it anymore. You can also look at the President who is a non-WASP. What has changed is that WASP people are no longer structurally enshrined at the top of the power structure. In previous centuries laws literally made white Protestant men the rulers of the nation. As migrants moved into the US they slowly accumulated power, money, and voting rights, and used them to improve their situation. This improving situation for migrant people weakened the position of WASP people relative to where it was previously. Now WASPs had to compete with other groups instead of being innately their superiors from a legal standpoint.

I usually explain it as a footrace. In the times gone past when WASPS were on top, the laws of the footrace only allowed three people to compete, and you were one of them. Even if you come in last place you're still getting the Bronze, so life is good. Then the rules change and they let in six people. Now you really have to compete, but you still have more practice than the three new people so you do better. Eventually they allow more and more people, and the newer people get more experience and you are routinely losing. Racers #4-6 now agree with you since it is a lot harder, we should go back to the old rules with just 6 racers, and maybe you agree with them just to have an ally. To you, the race is in shambles. To a lot of other people it's just getting interesting. People are running faster than ever, and the real winner is on the track instead of watching from the sidelines, or running in a special side race. Sidenote: This analogy is not an endorsement of the unregulated free-market!