Highlight the text (not the marker) and change the "measured value" checkbox to "custom value" and you can add a suffix in the box on the right hand side. Or you can just type in a new value if it needs to be a prefix.
Cameron Hestler, Architect
Archicad 27 / Mac Studio M1 Max - 32 GB / LG24" Monitors / 14.5 Sonoma