xgx_scale_y_percentchangelog10: percentchangelog10 transform for the y scale.
Description
xgx_scale_y_percentchangelog10 and xgx_scale_x_percentchangelog10 are designed
to be used with percent change (PCHG) from baseline data (on a scale of -1 to +Inf).
Common examples include
It is used when you have a wide range of data on a percent change scale,
especially data close to -100