Global colour % changes to full

Hello,

I am using global colours and have made a set of greens by changing the % in the colour window. I am working in CMYK. However, when I use those greens to change colours globally, the % does not translate to the global colour change and stays as 100% of the orginal green. I have attached a screenshot showing this.

How do I preserve that % change when using global colours?

Thanks

Gio