weird behaviour of automatic axis scaling?

Dear gurus,

try this scenario...
in column A create 100 values of "8,8" and in column B create also 100 values with value of "7".
For those two columns, create simple line chart.

now, you will see that there are just two lines in the chart, one in 8,8 value, another in 7.
However automatic scalling of Y axis starts at 0... so both lines are at the top of chart .

Now, when I change the B column values from 7 to 7,334 then the scalling updates correctly and Y axis is starting from 6,5... so all area of chart is filled.

Why is this behaviour? why "7,334" is the limif for this scalling?
and mainly, what can I do with that? without using VBA to change the axis minimum, and without manualy setting it?

Thank you