If you double click the y-axis and then select the Scale tab, is the
'Auto' checkbox next to 'Maximum' checked? If so, XL is using auto
settings.

If not, it is possible you (or someone else) designated a custom chart
as the default chart. This custom chart has the 'auto' turned off.
Check Chart | Chart Types... | Custom types tab | in 'Select from'
select 'User-defined'

--
Regards,

Tushar Mehta
www.tushar-mehta.com
Excel, PowerPoint, and VBA add-ins, tutorials
Custom MS Office productivity solutions

In article ,
says...
Whenever I created a chart, the Y-axis maximum value always defaults to a set
value of 5000, i.e. not an "auto" value. This is regardless of the actual
data values. The minimum, major and minor unit values still work in full
"auto" mode. Any suggestions where I can reset the maximum to work as full
"auto" also?

Thx.