Brazil had a perfect leading indicator of future economic activity, which was the number of passengers on the Rio-São Paulo flight, normally businessmen. I suspect the New York - Washington flight used to be a predictor in the 50's.
It is less perfect now that the economy is much more diversified. However, it is still worth looking at such indicator. I have just traveled to Rio to make a Betting On Brazil presentation on a Wednesday, and the flight was 100% full. And Wednesday is a lull day; Monday and Tuesday mornings and Thursday and Friday evenings are peak times -- not Wednesday afternoons.
I'll try to find this February passenger statistics when they come out in March. It will be a delightful surprise.