Count how many were built prior to the past 10 years.
2.
And the vast majority of those were built within the past 5 years.
The city sprung up from virtually nothing in less than a decade. There's not many cities in the US where even just 5 of the 50 tallest buildings were built within the past 10 years (in NYC it's 9), let alone virtually all of them.
The little city of Dubai is spending a whopping $50 billion a year on contruction projects -- far more than the rest of the Middle East combined. For every high-rise building that it has built, it's got 3 more in planning or under construction right now -- it's got three hundred skyscrapers being built right now, NYC only has about 100.