For me, getting married at a young age will not make the Economy to be poor. I have never heard any studies that will justify this statement. I met a lot of young couples who had been successful in their lives. so I totally disagree with this.
That is just one thing! As all these things depends on the two people and how they are able to come together to grow in their lives. You can be old, wretched, married and still become a liability at the end, and you can be young, vibrant, and well to do for yourself, so it is not really about the age or when you get married, as long as you are matured enough, you can take care of a family to some pretty good extent and you both can do great for yourself, I do not see a problem in marrying young at all. Economic problem is basically rooted from the country's leadership most of the time.