Provided below are the sales (in millions) for 27 random Chick-fil-A restaurants.

1.971
2.335
2.969
3.357
3.414
3.566
4.148
4.262
4.687
4.851
4.917
4.996
5.098
5.152
5.458
5.421
5.732
2.250
5.768
6.045
6.156
6.165
6.412
6.468
3.828
8.338
7.084

Please find the IQR for this sample in millions of dollars. Round your answer to the third decimal place.