According to a survey, 78.9% of Taylor Swift's albums sales are in US, the 22.1% of it is outside the US.

Despite being called a "World Tour" the '1989 World Tour' did not come to many countries of South America and Asia.

Katy Perry 3 albums released = 9 #1s Taylor Swift "5 albums released multiplied by 2" = 8 #1s

The '1989 World Tour' grossed $200M out of $250M in North America, that means it only grossed $50M outside the US.

1989 7th Single New Romantics didn't top the Hot 100 top 15, something 'Teenage Dream' and 'Loud' failed to achieve.

Taylor Swift is one of the best VOCALIST today.

Taylor Swift didn't have a #1 single on her first 3 albums, something Gaga, Rihanna & Katy Perry failed to achieve.

Taylor Swift's best-selling single still sold far less than Lady Gaga's 2nd best-selling single.

Taylor Swift's best-selling single still sold far less than Katy Perry's 3rd best-selling single.

UK #1s Rihanna: 8 Beyoncé: 5 Katy Perry: 4 Lady Gaga: 4 Ariana Grande: 2 Taylor: Swift