14 bit NEF (RAW) or TIFF for HDR

Which would give the highest bit depth?

The User Guide on page 402 lists file size:
14 bit RAW Uncompressed = 25.3 MB
TIFF (RGB) Large = 36.5 MB

page 56 Quote:
"Record uncompressed TIFF-RGB images at a bit
depth of 8 bits per channel (24-bit color)."

Does 14 bit RAW mean 14 bits per channel (42 bit color)?

 

Thanks, then for HDR RAW 14 bit would be better and have a smaller file size than TIFF