Label escape code for metric prefix

It's great that Igor automatically generates metric prefixes for axis labels when waves have a specified units (e.g., when plotting a wave with units "A" as for amps, if the data have values ~10^-9, the axis is labeled nA). 

However, I almost always find that I cannot take advantage of this because I use 2D waves where different columns have different units. For example, one column might be a time-varying current that I measured in amps, another column might be that current converted to conductance in siemens. The former needs wave units of "A" and the latter needs "S", which can't be specified.

In the absence of a wave unit, axes are instead labeled x10^-9 for valuse ~10^-9. I would like a way to automatically plot "n" in such cases.

It would therefore be great to have a new axis label unit escape code (in addition to the present \u\U\E\e, etc.) that provides the metric prefix. (This would also provide automated metric prefixes for waves that don't have wave units, and so I think it would be generally useful)