I have a series of VBA generated plots with dual axes.
The data charted is best represented with a logprimary axis scale and a
log secondary axis scale.

For most datasets this is fine, and has the left/primary axis marker
'1' aligned horizontally with the right/secondary axis marker '0'; all
correct and how I want it it.

However, when an original value is less than 1, the primary log axis
responds appropriately by adding another log unit ('0.1') to
accommodate the data. The problem the plot then has is that this new
minimum on the primary log scale is aligned horizontally with the
right/secondary axis marker '0', which is not correct at all.

How can I code that the minimum axis value on the secondary axis (which
is invariably zero) will always align horizontally with the value 1 on
the primary log axis, regardless of how many log units this primary
axis requires?

Thanks in advance for your suggestions.

Matthew