Greetings and Happy New Year!

I ripped all my CDs years ago using EAC with REACT in FLAC format and during the process Replaygain (RG) was included in the ripping process. One of the tags for the RG process is Reference Loudness (RL), 89dB . When using Foobar2000 for RG, the RL is not tagged. Isn't the RL required in order for RG to work properly? Any and all info on this is appreciated.

Thanks in advance.