Even though you only see one number on the horizontal axis, it is still a range of information.

Bar 1 has an interval of 139.5 - 149.5

Bar 2 has an interval of 149.5 - 159.5

Bar 3 has an interval of 159.5 - 169.5

Bar 4 has an interval of 169.5 - 179.5

Bar 5 has an interval of 179.5 - 189.5

Bar 6 has on interval of 189.5 - 199.5