According to the CTBUH, there were 38 skyscrapers over 800' tall in the US at the close of the 20th century (tragically, the two WTC twins would soon be lost on 9/11, making for 36 that still survive).
US Skyscrapers over 800 ft. In 1999: 38 (36 still standing)
New York: 12 (10 still standing)
Chicago: 9
Rest of America: 17
- Houston: 3
- Atlanta: 3
- Los Angeles: 2
- Philly: 2
- Dallas: 2
- Seattle: 1
- Cleveland: 1
- Charlotte: 1
- San Francisco: 1
- Pittsburgh: 1
Since then, a further 64 800-footers have been built (or currently U/C) in the US according to the CTBUH.
US Skyscrapers over 800 ft. built or U/C since 2000: 64
New York: 38 (includes 1 tower in Jersey City)
Chicago: 12
Rest of America: 14
- Miami: 5
- Philly: 2
- San Francisco: 2
- Austin: 2
- Los Angeles: 1
- Seattle: 1
- Oklahoma City: 1
Total US skyscrapers over 800 ft. built or U/C: 100
New York: 48 (includes 1 tower in Jersey City)
Chicago: 21
Rest of America: 31
- Miami: 5
- Philly: 4
- San Francisco: 3
- Los Angeles: 3
- Houston: 3
- Atlanta: 3
- Austin: 2
- Dallas: 2
- Seattle: 2
- Cleveland: 1
- Charlotte: 1
- Pittsburgh: 1
- Oklahoma City: 1
So there are now a total of 100 800-footers in the US (including U/C), but 48% of them are in New York, and a further 21% of them are in Chicago, meaning 69% of America's big towers are located in just those two cities.
here's a fun little chart comparing the 100 tallest skyscrapers in the US today with how things stood back in 2000.
The 100 tallest US skyscrapers, 2000 vs. today:
city ------------ 2000 ---- Current --- change
New York ------- 28 ------- 48* -----
+20
Chicago --------- 13 ------- 21 -------
+8
Miami ----------- 1 --------- 5 -------
+4
Philly ------------ 4 --------- 4 ------- 0
San Francisco --- 3 --------- 3 ------- 0
Atlanta ---------- 6 ---------- 3 -------
-3
Los Angeles ---- 10 --------- 3 -------
-7
Houston -------- 10 --------- 3 -------
-7
Austin ---------- 0 ---------- 2 -------
+2
Seattle ---------- 4 --------- 2 --------
-2
Dallas ----------- 5 --------- 2 --------
-3
Oklahoma City - 0 ---------- 1 -------
+1
Charlotte ------- 1 ---------- 1 --------- 0
Cleveland ------- 2 --------- 1 --------
-1
Pittsburgh ------ 2 ---------- 1 -------
-1
Detroit --------- 1 ---------- 0 --------
-1
Indianapolis --- 1 ---------- 0 --------
-1
New Orleans --- 1 --------- 0 ---------
-1
Boston --------- 2 ---------- 0 --------
-2
Denver --------- 3 --------- 0 ---------
-3
Minneapolis ---- 3 ---------- 0 --------
-3
(*) NYC's current total includes 1 tower in Jersey City.
source: CTBUH database