Gestalt Law :
- Right-align a block or column of whole numbers or of whole numbers and text.
- Left-align a block or column of whole text.
- Align numbers at the decimal point (or imaginary decimal point).
What excel defaults to :
What's wrong with the above diagram ?
According to Gestalt Law of Proximity our brain does not associate them if we left align column headers on numerical columns.
Other possibilities :
In the above diagram i aligned headers (Q1,Q2,Q3) and numerical values to the left here the problem is the eye has to search for the decimal point to get to the ten, hundred or thousand digit, this makes comparing numbers quite difficult if not impossible when many numbers are involved.
Here the headers (Q1,Q2,Q3) and numeric values are arranged at center If you keenly observe same problem will occur the eye has to search for decimal numbers which is not a best practice if we have huge numbers.
The above alignment is the best practice because we can easily find out what the number is so, it concludes that " Numbers should always to the right ".