How long can an excellent company keep up unstoppable growth rates? That's a question Nu Holdings' (NU -1.39%) investors and followers have been asking for some time. It has reliably grown its business by triple- and high-double-digit rates since it went public in 2021, and it's been highly profitable for more than two years now. But the market was a bit disappointed in its earnings report last week, and the stock dropped about 10% after the report.Investors shouldn't be too worried; Nu stock is still up 79 ...